Interesting talk about how the arduino (open source programmable device) is being used in all sorts of applications ranging from earthquake detectors, radiation monitoring in Japan, to a chair that tweets whenever its occupant farts, and a house plant linked to the web so that people can water it when it's too dry and so on.
A nice cat feeder is also shown that uses microchips in the collars of cats to recognise which cat is nearby and then activates old CD-tray mechanisms scavenged from PCs to expose the correct feed to the correct cat.
Massimo Banzi: How Arduino is open-sourcing imagination | Video on TED.com