Atmel AVR Microcontroller

I just got an Atmel AVR microcontroller development board in the mail, and have started playing around with it. Hobbyists use these for all kinds of things - from robotics, to data acquisition devices, to lighting modules, etc. Just Google "AVR projects", and you will see what I mean. I've been interested in learning about using microcontrollers for quite a while (ever since Dirk starting building a robot with them in 2001), but for some reason I just haven't buckled down and -tried- them yet. Last night I managed to write code and wire up a circuit to light a single LED. This would be the equivalent of a "Hello World" program in another programming language. It's a humble beginning, but I've already got ideas for lots of cool projects I can build with this thing!