I'd like to make an optical sighting mechanism for my camera for more reflexive shooting. Basically, I'd like to have a leveled low-power laser that is "on" until the camera is shooting (detected through the hot shoe), at which point the laser turns off so it isn't in the picture. Even better: non-visible laser that can only be seen through some kind of sunglasses-style goggle system, so other people's shots don't get messed up.

• This post on photo.net has some starting information on the hot shoe pinout, which is pretty old. The center post is standard, but the smaller ones are proprietary to camera manufacturer.

• Some interesting background information on PC cords, which is another method of triggering strobes.