TidyUp-Mail software is designed for Russian, Ukrainian, and Belarusian users but can be useful for anyone who reads emails.
It's important to note that all the documentation is in Russian, so you'll need to check for a local Russian hacker to help you out. Overall, if you're looking for a way to not only clean up your mailbox but also make xterm happy, then tidyup-mail is the software for you.
Version 0.12: N/A