LINUX:  a powerful, fast and reliable backup & sync tool

Pinta is a drawing/editing program modeled after Paint.NET. It's goal is to provide a simplified alternative to GIMP for casual users. It is currently early in development and works on Windows, OSX, and Linux. 

Linux Mint is an extremely popular Ubuntu based linux distribution that rivals it's predecessor when it comes to adoption rates. With the recent release of version 8, Linux Mint promises even more improvements.

BackTrack consists of more than 300 different up-to-date tools which are logically structured according to the work flow of security professionals. This structure allows even newcomers to find the related tools to a certain task to be accomplished. New technologies and testing techniques are merged into BackTrack as soon as possible to keep it up-to-date.

Ekiga (formely known as GnomeMeeting) is an open source VoIP and video conferencing application for GNOME. Ekiga uses both the H.323 and SIP protocols. It supports many audio and video codecs, and is interoperable with other SIP compliant software and also with Microsoft NetMeeting.

HandBrake is an open-source, GPL-licensed, multiplatform, multithreaded video transcoder, available for MacOS X, Linux and Windows.