No, that's not a typo, it does actually say Muxtape. If anything is stroking my nerd chub right now, it's this, hardcore. The concept is extremely simple. Pick a user name, upload up to 12 songs (that you have permission to use, of course), and share away! The interface is simple and well designed, the functionality works great, and aside from the occasional problem that could arise from allowing it to play over and over for an extended period of time (a.k.a Muxtaping myself to sleep the other night), it plays like a charm. Not to mention, unlike most music "players," it involves absolutely no flash, which means it downgrades quite nicely on my iPod touch.
I'm fascinated by this project from an idea standpoint but I also have a number of questions that hopefully will be answered soon.
All questions aside I'm going to be keeping my eyes on this and probably making a few more mixes with the various e-mail addresses I hold on to. If you get around to making one, share it with me! I've already learned about tons of new music just from a few days of poking around. Also, if you're bored and looking for something to listen to, check out my first Muxtape.