Droplet photography (link translated from French) often produces simple and beautiful images, but timing the exposure can be tricky. Snapping the photo too early or too late can cause you to miss the action, which only lasts a fraction of a second. EquinoxeFR (the people behind the Asus WL500GP audio hack) came up with a solution to this problem using a circuit with an ATmega168 running an Arduino environment. The circuit controls a syringe that contains a liquid and is triggered remotely to release a drop into a darkened chamber. A camera with the shutter open is attached to the chamber, and before the droplet hits, it crosses an IR sensor that triggers the flash to go off a few milliseconds later, capturing the unique crown shape of the impact. No schematic is available as yet, but comments at the bottom of the post suggest one will be coming soon.