I have used Posi-taps and Posi-loks very successfully to install everything from a radar detector and iPod dock to my car to a Flash 2 Pass garage door opener and integrate tail light/turn signal to my bike.
These are back in stock at WebBikeWorld. I just purchased kit 15 with two fuse holders. Thought I would let everyone know because I think a few ppl were interested when they sold out before.