There's an article on Gareth Brooks' light painting in this month's photography monthly, with some stunning images.

I don't have the gear that Gareth has, but I figured I could create a quick and dirty iphone app to act as a lenser tool. It worked OK, but it really is just work in progress - i'm sure I could modify the app to generate some more interest shapes.

I suspect it may work better with an iPad. It almost gives me an excuse to buy one :)