Sounds like a really cool street trick. . .simple, to the point, confusing to a viewer, and easy to link with other tricks. . .I like. . .You don't mind if I toss a few ideas around in my mind, do you?
Jeeze, that's the second trick today that I figured a solution to and get stood up by another magician =/ (First was a ashes on arm done on the spectators arm. . .I still like my method better though >.>)
naw i dont care.see the thing is i dont have a method yet so i was wondering if u guys could help me invent it.ok well help me figure out a method for it
Well, my immediate reaction was to say that if you could, depending on the surface this may work, get some clear tape down or a small amount or rubber cement then rub it off with very little detectable left-overs, it would work. . .but there are a few limitations on that. (Just my first impressions, give me a day and I'll have a better idea.)
The issue with that is that special ink requires special pens and prodcution. . .if you're willing to put the work in that's fine, try and somehow get a gel based colored substance in for the ink (think something like chapstick). . .or that stuff that you used to get as a kid that was colored water that faded away as it dried. . .you'd have to act fast though.
You could use erasable ink, and use a thumb tip and modify and make it have rubber on it, or if there was a thumb tip that was rubber it already ( probably is, I've never bought one before ) and then you could erase the ink and pretend your rubbing the ink, you just need something to distract them so you can ditch the thumb tip, like a routine.