Mutt for OSX 1.4 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The program lies within Communication Tools, more precisely E-mail. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software.
From the developer:
Mutt is a small but very powerful text based program for reading electronic mail under unix operating systems, including support color terminals, MIME, and a threaded sorting mode.
You may want to check out more software for Mac, such as MPlayer OSX Extended, QuickShow OSX or Same OSX, which might be similar to Mutt for OSX.