filegive easily sends or receives files point-to-point, with authentication and ciphering, and the other side only needs a Web browser. No third party server is involved in the transfer. It can use common NAT traversal protocols like uPnP and NAT-PMP, manually forwarded ports, or a public ssh server.
robonobo is social music sharing and downloading software. It allows you to share your friends' music libraries and playlists, stream the audio instantly, and download the file in the background so you can burn it, export it to your music player, or do whatever you want with it. You can import your friends list and share links to your playlists via Facebook and Twitter.
RHash is a utility for computing hash sums and creating magnet links. It supports CRC32, MD4, MD5, SHA1/SHA2, Tiger, TTH, Torrent BTIH, AICH, ED2K, GOST R 34.11-94, RIPEMD-160, HAS-160, EDON-R 256/512, WHIRLPOOL, and SNEFRU hash algorithms. Hash sums are used to ensure and verify the integrity of large volumes of data for long-term storage or transferral. RHash can calculate magnet links and EDonkey 2000 links. It can update existing hash files by adding sums of files missing in the hash file. It can output in a predefined (SFV, BSD-like) or user defined format. It can process directories recursively.
Bitcoin is a peer-to-peer electronic cash system that is completely decentralized, without the need for a central server or trusted parties. Users hold the crypto keys to their own money and transact directly with each other, with the help of a P2P network to check for double-spending.
TomP2P is a P2P-based high performance key-value pair storage library. Each peer has a table (either disk-based or memory-based) to store its values. A single value can be queried or updated with a secondary key. The underlying communication framework uses Java NIO to handle many concurrent connections.