This is a list of applications I use on a daily basis. My main intention with these is to prove for myself that there is a good open source alternative to most common applications usually found on a regular computer. If an application of the list is not free to use I will mark it in italic. The list is split into Windows, Mac OS and Linux for simplicity.

Windows

Foobar2000
Audio player for windows
http://www.foobar2000.org
Replace: Winamp

Launchy
Application Launcher by a simple keystroke
http://www.launchy.net/

Starburn
Free software to burn cds and dvds.
http://www.rocketdivision.com/starburn.html

Notepad++
Editor
http://notepad-plus.sourceforge.net/uk/site.htm

FreeMind
Mindmaping
http://freemind.sourceforge.net/wiki/index.php/Main_Page

EverNote
Save your notes and texts for later search.
http://evernote.com/

Miranda
Instant messaging client
http://www.miranda-im.com
Replace: ICQ, MSN

Putty
Console-klient
http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html

uTorrent
Small and easy BitTorrent application.
http://www.utorrent.com/index.php

TeXnicCenter
TeX-editor
http://www.toolscenter.org/

PhotoRec
Tool to recover files lost in formatting or losses of harddrives.
http://www.cgsecurity.org/wiki/PhotoRec

phpDesigner
php/sql/html/css editor
http://www.mpsoftware.dk/phpdesigner.php
Replace: Zend Developer

PSPVC
Convert videofiles to portable format.
http://pspvc.nswardh.com/index.php

WriteMonkey
Zenware, writing application
http://www.wrtitemonkey.com/

Inkscape
Freeware alternative to Illustrator
http://www.inkscape.org
Replace: Adobe Illustrator

Open++
Add anything to right-click-context
http://www.tucows.com/preview/515698

Mac OS

None yet.

Linux

None yet.