Imapfilter is a mail filtering utility written in Lua which connects to one or more IMAP accounts and filters on the server using IMAP queries. It is a lightweight command line utility, the configuration can be versioned and is simple text and it is very fast.
Ry’s Git Tutorial is a complete introduction to distributed version control with a focus on practical command line usage. We explain Git’s robust branching, merging, and collaboration capabilities from the ground up, so prior experience with centralized systems like SVN or CVS is not required.