zfec is a fast, portable, and programmable implementation of erasure coding. It includes a C library, a Python library, and a command-line tool. Erasure coding is also known as "forward error correction", which is the generation of redundant blocks of information such that if some blocks are lost then the original data can be recovered from the remaining blocks. The RAID-5 algorithm is an erasure code, but while RAID-5 can recover from the loss of any one element, zfec can be parameterized to choose in advance the number of elements whose loss it can tolerate.
Korallenriff is a program that collects input from different network sources and stores their data into one database. For example, it can receive POP3 mail or can fetch NNTP groups and store the received messages in a database. One can then, for example, use the database data within a Web site to display the latest postings of a newsgroup or to create an online mailing list archive. Another possible use would be to build a blogging-software where one can post via email.