It took Steven Silton two hours and 150 tries to capture this amazing photograph of a water drop showing an MC Escher painting.
The hardest part was focusing, in the set up picture I posted in the first comment you can see a piece of string above the eye dropper. I would let that hang down off the eye dropper and focus on that, then move it and squeeze the dropper and the shutter at almost the same time. [#]
He used a Canon 7D and 60mm macro lens, shooting at ISO 640, f/2.8, and 1/250.