Does mplayer play music files? Might be the solution for my little project... (I'll do some ing laterf

Bastard phone. :((

Yes, it does.

Grand - I didn't have time to do much googling about it last night, but it looks like it supports a touchscreen interface - do you know if it supports the small screens out of the box with an appropriate small screen GUI?

Mine was a generic 3.2 incher, John, but it worked fine with Waveform's Raspbian image here, or you could just install the driver on the same page.

I've been experimenting with a version of Jessie lite (the newer version of Raspbian custom packaged from adafruit with their drivers built in), which has been working well with the screen. I just need a small screen GUI for an MP3 player to go with it.

I've been checking out a few more guides, searching less specific criteria and found this guide where the dude has XBMC running on a (albeit larger) touchscreen in his car. I've not read through the whole thing properly yet, but I'll hopefully be able to cobble something together from his guide tonight. 

The image I linked to does a good job of forcing the GUI to 320x240.  It would be funkier still if I could force windows to a similar size.