An artist already created a Twitter-controlled cockroach. If that was too squicky for you, then maybe you'll feel better about commanding Paintbot instead. Paintbot from iStrategyLabs is a Twitter-controlled paintball gun. Tweet the right hashtag and enjoy the knowledge that you've just made a mess you don't have to clean up.
You can get in on the paintball action when the gun is online by tweeting with the hashtag #islpaint. Unfortunately, Paintbot has to be taken offline periodically for clean-up. It has a tendency to splatter.
The target is an unfortunate whiteboard which just stands there and takes the abuse without complaint. It does have an illustration on it that sums up its futility of existence as a target for tweeting paintball shooters.
Paintbot is part of iStrategyLab's work with what it calls "social machines." These devices let activities that happen in the social media realm impact events in the real world. Previous projects included a social fridge and a Foursquare-activated drinks cooler. The paintball gun works thanks to an Arduino processor.
Paintbot was created in less than 12 hours, but it should have a long life ahead of splashy, colorful mayhem. Whiteboards the world over will tremble at the mention of its name.