/Tab - The simple way to split a bill among friends.

SpamAssassin - Use this program to "Unspam" your mailbox(es).

Splitwise - Splitwise is a free tool for friends and roommates to track bills and other shared expenses, so that everyone gets paid back. On the web, iPhone, and Android!

MailScanner - MailScanner is a open source email security system design for Linux-based email gateways.

Splittable - Shared living made simple

Rspamd - Rspamd is an advanced spam filtering system that allows evaluation of messages by a number of rules...