There's a popular computer discussion group that I belong to that has a neat point system. The original poster awards points to those that respond to his/her post based on the value of the response. For example, "you solved my problem" = 10 points; "thanks for the tip, but that's not what I was getting at" = 1 point; etc.
Just an idea since that, on TBN, there are some posters who seem embarassed to have acquired their respective titles because they claim most of their posts were questions and not answers.
I realize that the member titles (gold, platinum, etc.) are not a measure of one's knowledge - they simply indicate how many posts that person has made (except of course for Star members and Moderators). This would change that (free hats for 10 000 points!)