SiMP
SiMP (Simple Mail Parser) is a procmail-like mailparser, except that it's much more easier to configure. With SiMP you can automaticly store incoming mail in seperate folders, remove junkmail, send a reply, forward the mail, etc.
It has been tested with Sendmail and Postfix as a mailserver and Pine as the mailreader, but it is likely that SiMP will work with other mailservers and -clients.