IndigoWidget is a Dashboard widget for controlling Indigo Home Automation software.
Home automation is great. Perhaps not necessary (ok, definitely not necessary) but I've always gotten a big kick out of writing software that makes things in the world turn on, move, shake, blow up, or otherwise do something real. It's like magic to me, even when I wrote the code and understand all (most) of the physics behind it.
Now you can control your lamp sitting on your desk just by hitting F12 and then flipping the switch or sliding the slider! Well, ok, better example - turn off all the lights outside before you go to bed. Or, get that fresh pot of coffee brewing, straight from your dashboard!
The project is free of charge, and open-source (well, like most widgets - but this is actually open-source licensed). So have a go!