CUI32 PIC32MX Development Stick
The CUI32 is a new version of the CREATE USB Interface, based on a 32-bit PIC. The CUI32 ships with "StickOS" installed as its default firmware - this is an full operating system (!) created by Rich Testardi with an on-board BASIC compiler, line editor, debugger, profiler, and simple file system to create new firmware programs and run them, without having to install any software on your host computer... All that's needed is a standard terminal emulator (Hyperterminal/Teraterm on windows, the "screen" command in the OS X terminal, etc.)!
StickOS is a very elegant approach for beginners, and also works great as a quick prototyping environment for advanced users - see a couple of examples (using a different microcontroller) here.
The CUI32 also ships with a standard bootloader pre-installed (in addition to StickOS), so you don't need a PIC programmer to write your own C programs either! All of Microchip's own examples from their USB framework can be compiled for the CUI32, and while these are more complex than a BASIC program written in StickOS, the CUI32 homepage and the Google Code wiki will allow anyone to share examples that are set up specifically for the CUI32.
Finally, since the CUI32 uses the same family of PIC32s as the UBW32 board, it is compatible with a lot of the resources that have been developed in this open source project as well, such as this host application for bootloading the board from OS X.
Dimensions: 4.0 x 1.7" (2.6 x 1.7 without prototyping area)