We should do better than that, and create a speculation game/competition. Everyone starts with 100 virtual bitcoins (is that an oxymoron too?) and trades them using mtgox prices. After a few months, we see who comes out ahead.
That sounds like a fun idea, but also sounds like a lot of work and would be hard to keep everyone "honest".
In any case, I'd play and just sit on my 100 coins

why would it be hard to keep them honest?
And yeah, it would be a bit of work, especially if you want to do it right, but a basic implementation might not be that hard. I think I will look in to it anyway.