Wireless Remote Release For Threaded Shutter Button - Any Out There?

A friend asked me yesterday whether I knew of a wireless shutter release of the kind that screws into the shutter button with the usual conical thread. My knowledge stopped at an air bulb release, which wasn't considered suitable. I've had a trawl of the web (unsuccessfully) so wondered if anyone here knows of such a device? Clearly it would need to have batteries on board at the camera end to effect a mechanical movement of the shutter button as well as at the transmitter end.
Any help gratefully received!
Thanks very much,
Steve

http://photo.net/large-format-photography-forum/00Ma9V

from 2007

Thanks - whilst my friend is looking for an 'off the shelf' solution, this could be an option if push comes to shove!
Best wishes,
Steve