Have any of you got your hands on these babies http://mbed.org/
? I am certainly not going to trow away my beloved Arduinos any time soon, but those mbed mircocontrollers seem really interesting. The features include 60Mhz/32bit ARM Cortex, 512kB flash, 32 MB ram, 3 UARTs, USB, ethernet, real-time clock etc. It has breadboard friendly form factor, although slightly larger than Arduino Nano. It has web-based C++ development environment. I looks to computer as an USB-stick, and uploading a sketch is simply copying the sketch in to it. The price isn't bad either, Farnell sells them at 54,69 , although they have none in the stock yet.