P2P Messenger .NET 

P2P Messenger is secure Instant Messaging client, working by Peer-to-Peer technology. It is fully decentralized and does not require any servers. Supports public-key cryptography
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eZ 

Simple, free universal viewer for PDF, CAD, 3D Models, Word, Excel, PowerPoint, digital photos: JPG, GIF, BMP, and more. Open multiple files of different type at once and tile to see them all on your screen at once. View compound .ez presentations.
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digital candy 

Digital candy is a great new program to search for files on the bittorrent networks giving you a better chance of finding what you require. It will search many sites at the same time, saving you time
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BigSpeed Net 

BigSpeed Net lets you set up a virtual private peer-to-peer (P2P) network with friends or co-workers in minutes. It combines transparent data transfer encryption with highly optimized data transfer, on-the-fly compression, user level access control.
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Twister 

Twister is a free program to find and download MP3 and other music files on the internet. Twister uses the top search engines available today. Twister is compatible with the major music players including Media Player, WinAmp and Sonique.
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No Hawkers - AntiSpam 

No Hawkers - Antispam is a peer-to-peer spam stopping solution. Using the same community technology that makes other products some of the largest sharing communities in the world No Hawkers brings the spam fighting effort into a new age.
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