With the enormous amounts of e-mail many people gather and the importance of e-mail messages in our daily work-flow, it is very important to be able to quickly deal with all that - in particular, to instantly find that one important e-mail you need right now. For that, mu was created. mu is a tool for dealing with e-mail messages stored in the Maildir-format, on Unix-like systems. mu's main purpose is to help you to find the messages you need, quickly; in addition, it allows you to view messages, extract attachments, create new maildirs, … See the mu cheatsheet for some examples. Mu's source code is available in github, and there is the mu-discuss mailing list. mu includes an emacs-based e-mail client (mu4e), a simple GUI (mug) and bindings for the Guile/Scheme programming language. - Matteo Marchelli