And by cheap, I mean in the $100-$500 ballpark.
I use Vado and Flip cams all the time as b-roll and bumper cams. They produce interesting cut away shots because you can stash them anywhere for a different perspective.
I’ve also used my iPhone 4′s camera as a main and b-roll cam for similar use.
We don’t have any Go Pro cams in our arsenal at OPUBCO. But here’s an example of strapping (or gaffe taping) a cam to the bottom of a skateboard. The result is a very low to the ground effect. And at least two destroyed cams. But a great video. Great idea.