Sometimes you need only a free and simple tool to accomplish your task. Sure, iTunes and its ilk all have random or intelligent playlist generators, but self-starters who have organized their MP3 collections by hand into a folder structure might only require a tool to randomize songs within selected directories. That, in a nutshell, is what the aptly named Random MixTape Maker does--no more, no less.
There are only three significant buttons on the main page of Random Mix Tape Maker: Create Playlist, Save Playlist, and Shuffle Playlist. Create simply gathers the songs (MP3 only) you've pointed the program to and randomizes a playlist, Shuffle re-randomizes the order, and Save saves a standard .m3u playlist (I told you it was simple). Other program pages allow you to define must-have songs that will be included on all lists as well as black-list songs so they do not appear on lists.
It's free and it's fast. And if you have the need, it's handy indeed.
This program is donationware. It is free to try, but the author accepts and encourages donations towards further development