Azureus

A powerful, but complicated BitTorrent client. So many features you'll lose your mind.
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VLC

Plays more video files than most players: Quicktime, AVI, DIVX, OGG, and more. Pretty good interface.
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MPlayer

Similar to VLC-- plays loads of video formats.
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Media Player Classic

Compact, but powerful media player. Plays anything under the sun. No install necessary.
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Media Coder

Great tool for ripping CDs, DVDs, etc and converting between tons of video formats.
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OpenOffice.org

Big, full featured suite of tools for word processing and spreadsheets. Compatible with and a free replacement for Microsoft Word documents. Also supports OpenDocument Format.
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AbiWord

A word processor. Leaner and quicker than OpenOffice. Compatible with Microsoft Word documents and OpenDocument Format.
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