Oh, another idea, how about making the quiz montly or bi-monthly, and it could have questions about things that have been discussed in the forums. It would show who's been paying attention, and who's not. I just think it would be fun. I know I love it when friends try to stump me with coaster questions!
Just remember, no stakes involved, just keep it as a fun thing to do.
-------------
I'd Rather Be Riding Rollercoasters
www.mycoasters.homestead.com/mycoasters.html