For a birthday celebration on cam...
I think some cam girls used to write down things on small slips of paper (not sure if it was a prize - like a vid or pic set, or an activity - like "Do naked jumping jacks"), and then slip them into balloons that haven't yet been blown up. Right before getting on cam, all of the balloons are blown up. And then in your room topic, you'll state that tips of __ tokens will pop a balloon...and you can win a prize (or an action). It's really up to you how you decide to do it, and what you decide to offer.
You could do some sort of raffle where every tip of 13 tokens (just used that as an example since your b-day is Aug. 13) gets the member a raffle ticket (Dollar Tree sells a pack of 250 tix for $1, or if you wanted a hard-to-find color like pink, they've got 'em on Amazon).
Whenever I felt like doing raffles a little differently from the usual "raffle ticket" method, I used one of those pink Bling Bingo games ($5 at a Five Below store) instead, because I love the color pink, and I just thought it seemed a little cooler and fancier.
I think the Bling Bingo game comes with 75 balls, and every member who tips __ tokens is assigned to one of those pink balls...which says something on it like "B 52." After all 75 of those balls have been assigned to tippers, that's when you can start cranking it and pulling out numbers. 75 balls means that there will be 75 entries. Let's say you make it 100 tokens per entry. 100 x 75 = 7,500 tokens ($375 in your pocket).
I've seen some models open up their birthday gifts (from MFC members who've sent gifts to their P.O. Box) on cam.