Arduino

I've been playing around with a neat little micro- controller develop- ment board called Arduino. It has built in I/O for sensing and controlling the outside world. A great development environment too; it only takes moments to set up the software under Linux or Windows.
So far I've lit up LEDs, generated a waveform for display on an oscilloscope, and run a DC motor using pulse width modulation. And it has all been very easy to learn the C-based programming language.
I'm working a laser display project right now for a friend. Soon I will be working on some "Mad Scientist" display ideas for Halloween.