Let's Make Robots!

Compatible.

What is your favorite Arduino compatible board?

I do like a lot of controllers (and I am sure there are more to come!)

On the subject of the Arduino:

What is your favorite Arduino (program / form factor) compatible board???

Mine is: The Uno32 because it is a fast Arduino and can be so much more (has a PIC 32 bit chip)! I still wish it was a 5V I/O board, but 3.3V is here to stay...