PC Magazine released a great list of 157 free software tools. Below I have pasted the beginning of the list, please visit http://www.pcmag.com/article2/0,2817,2260070,00.asp for the rest.
Windows | MacOS | Linux | Mobile This simplest of Adobe’s PDF programs lets you do just about anything PDF-related (besides create new ones), including online collaboration. It includes a host of features to aid users with disabilities.
Windows | MacOS | Linux Whether you’re recording or editing, Audacity is all about audio in practically any format.
Windows | MacOS | Linux The GNU Image Manipulation Program (GIMP) does most of what Photoshop does; the Gimpshop project (plasticbugs.com) even makes it look like Photoshop. Read our full review of The GIMP 2.0.
Windows | MacOS When you’re attached to the top media player in the land (iPod), success is a given. iTunes continues to build sales and refine its organization of songs, video, games, podcasts, and more. Read our full review of Apple iTunes 7.6.
Windows | MacOS | Linux You can spend a lot for Microsoft Office or nothing for this suite with full-function word processor, spreadsheet, database, presentations, even an equations editor. Read our full review of OpenOffice.org 2.3.
Windows | MacOS | Linux You’ll pay to call regular phones, but if you sign up all your friends, Skype provides easy (and even international) calls and video-conferencing for nothing. Read our full review of Skype 3.0.
Windows | MacOS | Linux Mozilla’s no-cost e-mail alternative is extensible, fast, and easy to master. And a wealth of free add-ons means there’s not much this program won’t do, from calendars to encryption. Read our full review of Thunderbird 2.
Linux This Linux-based OS comes with many of these Hall of Fame products (Firefox, OpenOffice.org) preinstalled.
Windows After a decade of playing music, the “skinnable” WinAmp has several versions, including one with full CD ripping and burning.