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.
eContent is a Web-based content management system for creating information systems, intranets, B2B, B2C, catalogs, and vertical portals. Written in Java for scalability, and based on open standards Struts and Expresso for stability, eContent integrates content management, scalable content and application delivery, resource management, workflow and personalization. It supports executables, all documents types, OLAP reports, Java programs, and legacy integration.
Echomine Feridian is an easy-to-use Java API that gives you quick and easy access to the XMPP network used in IM services such as Google Talk. The API allows you to communicate with Jabber/XMPP servers for sending and receiving instant messages, presence management, and custom extensions to the XMPP protocol.
FDT is an application for efficient data transfers that is capable of reading and writing at disk speed over wide area networks (with standard TCP). It can be used to stream a large set of files across the network, so a large dataset composed of thousands of files can be sent or received at full speed, without the network transfer restarting between files. It is written in Java, runs an all major platforms, and is easy to use.
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.
Rateless-coded Transport is a set of applications that use ground-breaking error correcting codes technology. They support fast reliable transmission over UDP, live content streaming and Internet multicast trees, duplex firewall transparency, ultra-fast reliable transport for WANs (up to 40-times faster than TCP), and optimal peer-to-peer multi-source download protocols.
uTorrent.py is a Python module for accessing the interface exposed by the uTorrent Web UI. Current features include getting and setting uTorrent parameters, viewing information and statistics on torrents and files, and setting torrent state and file priorities. Small example utilities are included. Note that the download file is a 7zip archive, not a PNG image.