You know I was thinking along the same way as Rui with Interval timer but gave up because it can't be set in MY SETTING's
Because as soon as you OK your settings. You have just turned Interval off.
So there are three options:
1) Lengthen the cable of the Ricoh CA-1
2) Bring a friend & train them in your camera ways of how you would like the shot.
3) Buy a HAMA remote cable, try it out & tell us if it fries the camera or works a treat.
I had a look at the site & it has nothing about Ricoh when put into there search box. http://www.hama.co.uk/tools/advanced_search/index.hsp
Electronics being electronics, I'm sure it can be done. Up to 30 meters out & CLICK, that's ya shot..
Be warned. Every camera company screws together there OWN operating system for their cameras.
If a Ricoh GX200 accepts a signal from a Ricoh CA-1 to half press & fire from USB. Then why not go wireless? Good luck..