Setting up a wireless camera/webcam for live shows?

Hey, I was wondering if anyone has experimented with the idea of using a wireless camera that showed what they were doing behind the decks for projecting during a live show? I think it would be a super cool feature especially with such fun devices as the launchpad and etc to let the crowd see whats going on.

http://www.youtube.com/watch?v=I0S8y04_qB4

This is what inspired me -- seeing the flaming lips live and how cool it was to amplify the human aspect of it in the simplest way possible - by making his face bigger! Applying this to a DJ set can make the crowd appreciate your work a lot more I think.. especially when normally all they can see is some dude (you) making strange faces while looking down at a metal box/boxes and a laptop.

Has anyone used specific systems for this or has any ideas that would work well? A webcam could be good if the cord was long enough to move around.. or alternately I have a battery powered spy camera w/ a composite (yellow cable) receiver box for output

In my heavy turntablism HipHop-Dj days, I used to mount a camera in the light rig above the set, and film a close-up of the two turntables and mixer, then project that on the wall. Worked really great, and shows the audience what's really going on a lot better.
These days I'm working with linking visual elements to musical parameters directly. Umm, it's complicated.

if your doing it wirelessly, dont do it cheaply. in my experience, 'consumer' wireless cameras are piss poor, as the voltage of the battery drops, the frequency drifts so every few mins you need to adjust the reciever