El software libre cada vez va ganando más terreno lo cual me alegra muchísimo ya que no por ser gratuito deja de tener calidad, al contrario, más personas trabajan en el día a día. Aquí en Desde un Blog apoyamos incondicionalmente el software gratuito. Les traigo una recopilación de muchos programas totalmente gratis:

3D Graficos:
3Delight Free - http://www.3delight.com/index.htm
Anim8or - http://www.anim8or.com/
Aqsis - http://www.aqsis.com/
Blender - http://www.blender3d.org/
Houdini (Free Edition) - http://www.sidefx.com/apprentice/index.html
Now3D - http://digilander.libero.it/giulios/Eng/homepage.htm
OpenFX - http://www.openfx.org

POV-Ray - http://www.povray.org/
SOFTIMAGE|XSI EXP - http://www.softimage.com/products/exp/v3/
Terragen - http://www.planetside.co.uk/terragen/
Toxic - http://www.toxicengine.org/
Wings 3D - http://www.wings3d.com/

Anti-Virus:
a-squared - http://www.emsisoft.com/en/software/free/
AntiVir - http://www.free-av.com/
Avast - http://www.avast.com/i_idt_1018.html
AVG - http://free.grisoft.com/
BitDefender - http://www.bitdefender.com
ClamWin - http://www.clamwin.com/

Anti Spyware:
Ad-aware - http://www.lavasoft.de/software/adaware/
Bazooka - http://www.kephyr.com/spywarescanner/index.html
Hijackthis - http://www.spywareinfo.com/~merijn/downloads.html
SpyBot Search & Destroy - http://spybot.safer-networking.de/
SpywareBlaster - http://www.javacoolsoftware.com/spywareblaster.html
SpywareGuard - http://www.wilderssecurity.net/spywareguard.html

WinPatrol - http://www.winpatrol.com/

Audio
Gungirl Sequencer - http://ggseq.sourceforge.net/pmwiki.php/Main/HomePage
HammerHead - http://www.threechords.com/hammerhead/introduction.shtml

Jesusonic - http://www.jesusonic.com/soft.php
KRISTAL Audio Engine - http://www.kreatives.org/kristal/index.php
orDrumbox - http://ordrumbox.sourceforge.net/
Tu2 - http://www.brambos.com/news.html

Reproductores de Audio:
1by1 - http://www.rz.uni-frankfurt.de/~pesch
Billy - http://www.sheepfriends.com/?page=billy
CoolPlayer - http://coolplayer.sourceforge.net/
DeejaySystem MK1 - http://www.deejaysystem.com/prod_mk1.asp
DeliPlayer. http://www.deliplayer.com/
Foobar 2000 - http://www.foobar2000.org/
iTunes - http://www.apple.com/itunes/
Jet Audio Basic - http://www.jetaudio.com/

Mixere - http://mixere.sourceforge.net/
Mixxx - http://mixxx.sourceforge.net/
monoRAVEik - http://www.mono211.com/monoraveik/mr1200.html
MoreAmp - http://sourceforge.net/projects/moreamp/
Musik - http://musik.berlios.de/
musikCube - http://www.musikcube.com/
QCD Player - http://www.quinnware.com/
Sonique - http://sonique.lycos.com/
Winamp - http://www.winamp.com/

XMPlay - http://www.un4seen.com/xmplay.html
Zinf - http://www.zinf.org/

Herramientas de Audio:
Audacity - http://audacity.sourceforge.net/

AudioShell - http://www.softpointer.com/AudioShell.htm
BeSweet - http://dspguru.doom9.net/
CDex - http://cdexos.sourceforge.net/
dBpowerAMP Music Converter - http://www.dbpoweramp.com/dmc.htm
EAC - http://www.exactaudiocopy.de/
Encounter 2003 - http://www.waschbusch.com/
GermaniXEncoder - http://www.germanixsoft.de/
K-MP3 - http://www.katarncorp.com/
KraMixer - http://www.kramware.com/

MP3 Book Helper - http://mp3bookhelper.sourceforge.net/
MP3 Tag - http://www.mp3tag.de/
Mp3 Tag Tools - http://massid3lib.sourceforge.net/
mp3DirectCut - http://www.rz.uni-frankfurt.de/~pesch/
MP3Gain - http://www.geocities.com/mp3gain/
mp3Trim - http://www.logiccell.com/~mp3trim/
MusicBrainz - http://musicbrainz.org/
Rarewares - http://rarewares.hydrogenaudio.org/
SoundEngine Free - http://www.cycleof5th.com/en/index.htm

TagScanner - http://xdev.narod.ru/tagscan_e.htm
The GodFather - http://users.otenet.gr/~jtcliper/tgf/
TigoTago - http://www.tigotago.com/

Quemado de CD/DVD:

Burn4Free - http://www.burn4free.com/
Burnatonce - http://www.burnatonce.com/
Burrrn - http://www.burrrn.net/
CDBurnerXP - http://www.cdburnerxp.se/
CDRDAO - http://cdrdao.sourceforge.net/
CDR Tools Frontend - http://demosten.com/cdrfe/
Deepburner - http://www.deepburner.com/
DVD Decrypter: http://www.dvddecrypter.com/
Easy Burning, DropCD & Audio CD - http://www.paehl.de/cdr

ImgBurn - http://www.imgburn.com/

Compresión / Decompresión:
7-zip - http://www.7-zip.org/
bzip2 - http://sources.redhat.com/bzip2/index.html

ExtractNow - http://www.extractnow.com/
FilZip - http://www.filzip.com/
Info-Zip - http://www.info-zip.org/
IZArc - http://www.florida.plus.com/izarc/
QuickZip - http://www.quickzip.org/
TUGZip - http://www.tugzip.com/
UPX - http://upx.sourceforge.net/
Zip&Go - http://www.handybits.com/zipngo.htm
Zipgenius - http://www.zipgenius.it/

Defragmentación:
DIRMS & Buzzsaw - http://www.dirms.com/
OpenVMS - http://www.execsoft.com/freeware/freeware.asp

Embellece tu escritorio:
AveDesk - http://www.aqua-soft.org/board/showthread.php?t=17372
CursorXP - http://www.stardock.com/products/cursorxp/download.html
Desktop Sidebar - http://www.desktopsidebar.com/

Filehand - http://www.filehand.com/
Glass2k - http://www.chime.tv/products/glass2k.shtml
Kapsules - http://kapsules.shellscape.org/
Konfabulator - http://www.konfabulator.com/info
Lost Goggles - http://www.lostgoggles.com/
MobyDock - http://www.mobydock.com/
Panorama - http://www.ivory.org/panorama.html
RunFast - http://www.idiogensoftware.com/runfast/index.htm

Samurize - http://www.samurize.com/
SlickRun - http://www.bayden.com/SlickRun/
Snippy - http://www.bhelpuri.net/Snippy/
TaskSwitchXP Pro - http://www.ntwind.com/taskswitchxp/
tclock2 - http://home.inreach.com/2tone/tclock2/tclock2.htm
Trip - http://trip.glenmurphy.com/
Weather Watcher - http://www.singerscreations.com/
WinRoll - http://www.palma.com.au/winroll/

Resumidores de Descargas:
Free Download Manager - http://www.freedownloadmanager.org/
Fresh Download - http://www.freshdevices.com/freshdown.html
LeechGet - http://www.leechget.net/en/
Retriever - http://www.halogenware.com/software/retriever.html

Star Downloader - http://www.stardownloader.com/downloads.php
Sun Download Manager - http://www.sun.com/download/sdm/index.xml
wackget - http://millweed.com/projects/wackget/
wget - http://xoomer.virgilio.it/hherold/
WellGet - http://www.wellget.com/

Seguridad y encriptación:
Axcrypt - http://axcrypt.sourceforge.net/
Blowfish Advanced CS- http://web.bsn.ch/lasse/bfacs.htm
Eraser - http://www.heidi.ie/eraser/default.php
File Shredder - http://www.sys-shield.com/fileshredder.htm
KeePass - http://keepass.sourceforge.net/
GnuPG - http://www.gnupg.org/
PGP Freeware - http://www.pgp.com/products/freeware.html

PicoCrypt - http://picofactory.com/picocrypt.html
TrueCrypt - http://www.truecrypt.org/
WindowsCleaner - http://www.winnowsoft.com/internet-eraser.htm

Manejadores de Archivos:

2xExplorer - http://netez.com/2xExplorer/
A43 - http://www.shawneelink.net/~bgmiller/
ExplorerXP - http://www.explorerxp.com
freeCommander - http://www.freecommander.com/index_en.htm
Gyula's Navigator - http://www.wanari.com/
JExplorer - http://home.megapass.co.kr/~woosjung/
MeeSoft Commander - http://meesoft.logicnet.dk/

Recuperación de Archivos:
PC Inspector File Recovery - http://www.pcinspector.de/file_recovery/UK/welcome.htm

Cortafuegos:
Jetico Personal Firewall - http://www.jetico.com/index.htm#/jpfirewall.htm
Kerio (Kerio Personal Firewall is FREE for home and personal use) - http://www.kerio.com/kpf_home.html
NetVida Safetynet - http://www.netveda.com/consumer/safetynet.htm
Outpost Firewall (version 1 is free) - http://www.agnitum.com/download/outpost1.html
SoftPerfect Personal Firewall - http://www.softperfect.com/products/firewall/
Sygate - http://smb.sygate.com/products/spf_standard.htm
Wyvern Firewall 2004 - http://www.wyvernworks.com/firewall.html

Zonealarm Basic firewall -

FTP Clientes:
CoreFTP - http://www.coreftp.com/
Filezilla - http://sourceforge.net/projects/filezilla
miFiles - http://www.simdata.com.au/mifiles.html
SmartFTP - http://www.smartftp.com/

FTP Servidores:
Cerberus - http://www.cerberusftp.com/
FileZilla - http://filezilla.sourceforge.net/
Golden FTP Server - http://www.goldenftpserver.com
Quick 'n Easy FTP Server - http://www.pablovandermeer.nl/ftp_server.html
SlimFTPd - http://www.whitsoftdev.com/slimftpd
TYPSoft FTP Server - http://en.typsoft.com/
WarFTPD - http://www.jgaa.com/

HTML Editores:

1st page 2000 - http://www.evrsoft.com/download.shtml
AceHTML - http://freeware.acehtml.com/download.html
Aracnophilia - http://www.arachnoid.com/arachnophilia/
FoxEditor - http://foxeditor.sourceforge.net/
HTML-Kit - http://www.chami.com/html-kit/
NVU - http://www.nvu.com/index.html
Selida - http://www.amaryllis.8m.com/
Trellian webPAGE - http://webpage.vendercom.com/
TSW WebCoder - http://www.tsware.net/

Visores de Imágenes:
Ahaview - http://www.aha-soft.com/ahaview/ahaviewfree.exe
FastStone Image Viewer - http://www.faststone.org/FSViewerDetail.htm
Irfanview - http://www.irfanview.com/
Picasa - http://www.picasa.com/content/download.php
Shell Extension - http://www.firmtools.com/products/shellextension/
SlowView - http://www.slowview.at/
XNView - http://www.xnview.com/

Mensajeros Instantáneos:
AMSN - http://amsn.sourceforge.net/index.php
Gaim - http://gaim.sourceforge.net/
Google Talk - http://www.google.com/talk/
IM2: http://www.im2.com
Mercury Messenger - http://www.mercury.to/
Miranda IM - http://www.miranda-im.org/
Pandion - http://www.pandion.be/
PSI - http://psi.affinix.com/
qip - http://www.qip.ru/
Skype - http://www.skype.com/
SIM - http://sim-icq.sourceforge.net/
TerraIM - http://terraim.sourceforge.net/
Trillian Basic - http://trillian.cc/downloads

Internet Explorer Acabados:
AM Browser - http://www.ambrowser.com/

AOL Browser - http://beta.aol.com/projects/aolbrowser/
Avantbrowser - http://www.avantbrowser.com/
Maxthon - http://www.maxthon.com/
SlimBrowser - http://www.flashpeak.com/sbrowser/sbrowser.htm

IRC Clientes:
BersIRC - http://www.bersirc.com/
BitchX - http://bitchx.org/download.php
HydraIRC - http://www.hydrairc.com/
NodeIRC - http://node.sourceforge.net/
TinyIRC - http://www.tinyirc.net/
XChat - http://www.silverex.org/news/

Programas para tu EMail:
Foxmail - http://fox.foxmail.com.cn/english/
i.Scribe - http://www.memecode.com/
Mahogany Mail - http://mahogany.sourceforge.net/
Pegasus Mail - http://www.pmail.com/
PopTray - http://www.poptray.org/

Thunderbird - http://www.mozilla.org/projects/thunderbird/

Programas Anti-Spam:
K9 - http://www.keir.net/k9.html
MailWasher- http://www.mailwasher.net/

POPFile - http://popfile.sourceforge.net/
SpamBayes - http://spambayes.sourceforge.net/
SpamPal - http://www.spampal.org/

Herramientas de Red:

CMDTime NTP Utility - http://www.softshape.com/download/
Ethereal Protocol Analyzer - http://www.ethereal.com/
Gencontrol - http://www.gensortium.com/products/gencontrol.html
hamachi - http://www.hamachi.cc/
NetMeter - http://readerror.gmxhome.de/
NetProfiles - http://netprofiles.danielmilner.com/
NMap - http://www.insecure.org/nmap/
Ntop - http://www.ntop.org
PingPlotter - http://www.pingplotter.com

PuTTY - http://www.chiark.greenend.org.uk/~sgtatham/putty
RAS Graph & Stats - http://forum.flashfxp.com/showthread.php?s=&threadid=2400
RealVNC - http://www.realvnc.com/
TightVNC - http://www.tightvnc.org/

Ultr@VNC - http://ultravnc.sourceforge.net/
WinSCP - http://www.winscp.com/

Officemática:
602PC Suite free edition - http://www.software602.com/products/pcs/download.html

AbiWord - http://www.abiword.com/
OpenOffice.org - http://www.openoffice.org/
qjot - http://www.xtort.net/xtort/qjot.php
TreeDBNotes - http://www.softviewer.com/treedbnotes/free_index.htm

Particionamiento:
Partition Resizer - http://zeleps.com/
Ranish Partition Manager - http://www.ranish.com/part/
SwissKnife - http://www.compuapps.com/Download/swissknife/swissknife.htm
TestDisk - http://www.cgsecurity.org/index.html?testdisk.html

Utilidades para PDF:
CutePDF - http://www.cutepdf.com/Products/CutePDF/writer.asp
Foxit PDF Reader - http://www.foxitsoftware.com/pdf/rd_intro.php
Free PDF - http://www.webxd.com/zipguy/frpdfdl.htm
Ghostscript/GSView - http://www.ghostscript.com/
PDF 995 - http://www.pdf995.com/
PDFCreator - http://sourceforge.net/projects/pdfcreator/
PrimoPDF - http://www.primopdf.com/

Enlace: Free Software