An Armduino would be great, especially since putting together the gnu development environment appears to be a bit complicated.
Code Sourcery has a light version of the GNU toolchain that is freely available. It doesn’t have the Eclipse IDE, but we don’t need it for Arduino IDE, as the action goes at the command line mode.
Westfw, Armduino or not, if you read about Cortex-M3 you will love it! They even have an evaluation board with one of their 64KB version, OLED display, pot, JTAG debugger, USB connectivity and limited editions of Keil or other development tools (the Code Sourcery version is not good as it offers a time limited release, instead of the code size limited of the other 2 tool vendors)… all for $49 in Digikey (726-1044-ND). It comes programmed with a video game that uses the OLED display and the pot. Or the Ethernet version for $69 (726-1054-ND).
I didn’t have much time to play with it, but looks very promising.
Just sharing my entusiasm for a new toy.