Ok, inspired by Stephen A. Lowe's comment about "playing Jon Skeet":

Make up cards based on the top N users, where N is maybe 100. Each player card has a score (based on rep, but adjusted to some scale, perhaps 1-10) and one or more tag+modifiers. e.g. John Fouhy might have a score of 3 and a modifier of python×2. Alex Martelli has a score of 8 and a modifier of python×5. Jon Skeet has a score of 10 and C#×5 and Java×5. Perhaps negative tags as well (this player knows nothing about xx).

Also make a bunch of tag tokens.

To start the game, shuffle the player cards and distribute them to the players. Also distribute the tags.

Each turn, one player must ask a question, by playing a small number of tags. Other players then answer by playing player cards face down. After everyone has played, the player cards are revealed and people score points.

Scoring would be based on the player's reputation and how well their tags match. Playing Jon Skeet on a C# question will score better than playing him on a C++ question, which will score better than playing him on a Python question. The highest scoring card played earns an accepted-answer bonus. The question scores based on the answers played in some fashion (the single highest score?).

Then the questioner role moves to the left and play continues.

Possible variations:

• The questioner gets to choose which answer to accept.
• Answers can be played in several rounds. Earlier plays get revealed, but have their modifier improved. e.g. a python question comes up and I play John Fouhy, while you pass. After my card is revealed, you decide to play S.Lott. My python modifier goes from *2 to *3 as fastest gun in the west.
• The player cards are separated into tiers, so that everyone gets (say) 2 A cards, 5 B cards, and 15 C cards.

Obviously I'm no game designer so there's a lot to be improved here, particularly the scoring. It shouldn't come down to "if you get the right top 2 or 3 cards, you win". But I think the idea has potential :-)