Brilliant project that uses a lava lamp to send randomly changing MIDI continuous controller signals. The creator uses it as a synthesizer controller on Reason and create some wonderfully unique sounds.
The basis of the project is a standard lava lamp (a large one will be easier to work with) and 12 light dependent resistors (“photocells”). I don’t even know what resistence mine are – they were cheap off ebay – the important thing is you can make pairs of the same resistance.
Check out the full set of instructions including Arduino code: Lava lamp MIDI controller (skriyl)