This is a cheaper but similar item to pocket wizards, similar functionality but at a fraction of the price. If you want to use your flash off-camera you clip the control unit to the hot-shoe on the camera and the trigger to the flash and away you go. The trigger doesn't manage the setup for you so you need to set the flash manually but lots of fun and interesting lighting effects once you can position the flash anywhere you like. I used this with a Nikon D50 but I think they should fit any hot-shoe camera.

$50 shipped.