I have a Lumix G1. It takes great photos, but a remote shuttle release would be nice. An Ardunio powered one would be nicer. http://www.robotroom.com/Macro-Photography-2.html has the circuit diagram and great instructions. I just need to find a 2.1 mm audio/mic jack now.
Update: Sadly it seems a 3 conductor plug salvaged from a broken Xbox headphone won’t work. D: