There are a lot of open source hardware products that have real world consumer applications, but the HexBright open source flashlight by Christian Carlberg is one the first true open source consumer electronics products. Not only is it a best-in-breed LED flashlight sporting a powerful CREE XM-L LED capable of putting out 500 lumens and can reprogrammed via USB to display any light sequence (high, low, blinking, SOS, etc.), but it is also one of the only open source hardware products you can give to your grandmother without any explanation (and who's grandmother doesn't want a shinny new flashlight?).
There are still 22 days left to order a first run HexBright on Kickstarter, but don't worry if you miss the deadline. I have a feeling these guys are going to be around for a while.
InMojo supports the Open Source Hardware Definition v1.0