The LED-clock is nearing completion (all that's left to do is to put it in a nice box and work on the software to display the patterns), and the design goals for the next project are already forming in my head.
There's this design-shop in Nijmegen, called "Deja Vu" (which, if you think about it, is a really odd name for a shop full of novelties). Their collection is rather fluid: the shelf life of the more expensive items they sell is rather limited. And thus, the stuff they display in their shop window changes a lot too.
A few years back, they had colored lighting panels on display. With four panels, they had made a square. Each panel had a light in it, that could change color. The panels were somehow synchronised and slowly changed color. So when panels A and C were changing from blue to red, panels B and D were changing from red to blue -- quite hypnotising. We really liked those, but they were awfully expensive!
Fast forward to today: I ordered 8 RGB-LEDs: LEDs that consist of three LEDs in one: one red, one green and one blue. By varying the amount of current that each LED gets, you can create different colors. (A sample circuit, which implements a basic color-cycle, can be found over at Bit-Tech.)
With a microcontroller, I could vary the amount of current each color gets, and thus the color of the LED... For the past hour or so, I have been lying awake in bed, thinking of how to control 8 LEDs with a single microcontroller, designing the circuit in my mind's eye, thinking of how to place the capacitators to ensure a smooth transition, and how to make the panels modular... I just can't sleep anymore, my head is too full.
On a brighter note: the LED-clock is still right on time, more than 24 hours later! We're throwing a party tonight, for our collective birthdays, and it'll be on proud display then. ;)