Hack-Factor: CD drive waters your plants
After 14 days of vacation, most potted plants look a bit droopy. Now, a nifty hardware hack consisting of a CD-ROM drive and a small Linux computer make sure that Bill Snitzer's plants will get watered in absentia, at least once. His control computer is a SheevaPlug, which is often sold on the continent as a Seagate incarnation called DockStar.
The small computer runs a Python script that spits out the CD tray with the command "eject", setting off the watering mechanism. Admittedly, you could ask your neighbours to drop by with a watering can or fill a bottle with water and stick it upside down into the earth, but Snitzer's technical solution clearly has a higher Hack-Factor.