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.
konspire is a searchable, distributed file-sharing system featuring resumable file transfers and fast, exhaustive substring searches of all hosted file names on the network. konspire is written using pure Java. Load from processing search requests is distributed throughout a dynamically connected network of servers. Several fault-tolerant features ensure system correctness and reliability.
nget is a commandline NNTP file grabber. It automatically pieces together multipart postings for easy retrieval, even substituting parts from multiple servers and newsgroups. It handles disconnects gracefully, resuming after the last part successfully downloaded, and caching of header data for quick access. It automatically downloads only as many par/par2 files as needed.
pftp allows you to send and receive files and directories recursively, send and receive standard input and ouput, filter your connection, set the net buffer size, set the bandwidth, send UDP datagrams unicasted, broadcasted, and multicasted (which is meant for AUDIO and VIDEO streaming), send data to another user and manage that data, perform a network test based on either UDP or TCP, and use optimized buffers for your Gigabit Ethernet links. pftp can start from command line, as a daemon, or by inetd. All features are supported for IPv4 and IPv6.