cfv is a utility to both test and create .sfv (Simple File Verify), .csv, .crc, .md5(sfv style), md5sum, BSD md5, sha1sum, and .torrent checksum verification files. It also includes test-only support for .par and .par2 files. These files are commonly used to ensure the correct retrieval or storage of data.
Pysync has both a demonstration implementation of the rsync and related algorithms in pure Python, and a high speed librsync Python extension. The pure Python is not fast and is not optimized, however it does work and provides a simple implementation of the algorithm for reference and experimentation. It includes a combination of ideas taken from librsync, xdelta, and rsync. The librsync Python extension is less flexible and harder to understand, but is very fast.
python-fchksum is a module used to find checksums of files (or stdin). It supports md5, crc32, cksum, bsd-style sum, and sysv-style sum. The advantage of using fchksum over the Python md5 and zlib(.crc32) modules is both ease of use and speed. You only need to tell it the filename, and the work is done by C code.
Ampache is a Web-based audio file manager. It allows you to view, edit, and play your audio files via the Web. It has support for playlists, artist and album views, album art, random play, playback via HTTP with on-the-fly transcoding and downsampling, vote based playback, playback via MPD and Icecast, an integrated Flash player, and per-user themes and song play tracking. You can also link multiple Ampache servers together using XML-RPC. Ampache supports gettext translations and has full translations into many languages.
BitTorrent is a tool for copying files from one machine to another. FTP punishes sites for being popular. Since all uploading is done from one place, a popular site needs big iron and big bandwidth. With BitTorrent, clients automatically mirror files they download, making the publisher's burden almost nothing.
JXTA technology is a set of open protocols that allow any connected device on the network ranging from cell phones and wireless PDAs to PCs and servers to communicate and collaborate in a P2P manner. JXTA peers create a virtual network where any peer can interact with other peers and resources directly even when some of the peers and resources are behind firewalls and NATs or are on different network transports. The project goals are interoperability across different peer-to-peer systems and communities, platform independence, multiple/diverse languages, systems, and networks, and ubiquity: every device with a digital heartbeat.