It's not the best idea in the world to go messing with outlets. But for a renter with only a teeny tiny bit of bathroom counterspace, that extra area to store a few lightweight toothbrushes is golden.
The way this crafter made this version is pretty specialized with laser cuts and this stencil, but you could use the project as inspiration to make a similar rig with whatever you've got handy. Check out the Flickr photo set to see the process first hand.
(Images: Flickr user Plusea.)