I have just discovered the new Maximite computer from Geoff Graham. http://geoffg.net/maximite.html This adds GW-Basic, a VGA screen, PS2 keyboard, USB port, SD/MMC storage, floating point maths, 20 I/O pins and more to your next PBP project for $75 or less.
I intend to use the Maximite as a co-processor within some products I have designed where I want a better human interface and file storage to SD/MMC.

The unit uses a PIC32 and is almost identical to the old TRS-80, all for $75 ready assembled at www.dontronics.com.

HTH
BrianT