Freelensing A Macro Lens
Our friend Destin (whom you may remember from his excellent cheapo high speed tutorial, heck I stalk this guy so much he'd probably called the cops by now), just came up with a quick little video about combining two favorable techniques: freelensing and reverse macro lens.
The idea is simple enough, pop your lens off the camera body, reverse it and hand hold it to get that killer macro. There is an adapter ring you can buy for this but, that would take half the fun off.
PS - this is highly not recommended for shooting on the beach ;)