Elektor magazine features in the current issue a DIY Segway called Elektor Wheelie. The system is build around a ATMEGA32 and has obviously a lot of mechanics. For sensing an ADXL320 (acceleration sensor) and an IDG-300 (gyro) are used. Looks like a fun project - and you have full access to the software (not sure what you really would program differently, perhaps one can tune it to get faster ;-)
Perhaps it could be a platform to motive embedded programming - with clear real-time constraints, as it hurts if you fall off… Next term we are teaching digital system design and programming of microcontroller systems - should we get one for the lab? Someone willing to built it?