http://www.funtrivia.com/knockout/subscribe.cfm
These can be quite challenging. Mondays are sign-up days for the FunTrivia Knock-out Weekly Tournament.
These are four rounds with each winner from the 16 people playing in each Tournament crowned on Saturdays.
And you are put in with people of about the same level of play.
I am at 31 weekly wins and 286 points. Some world class FunTrivia players have over a hundred or almost a hundred weekly wins.
After 25 wins your opponents are quite good most of the time.