List of Drupal based market makers ("prediction market" focused or otherwise)

I just realized there are now a few of these, so I wanted to create a list:

• Bookmaker which has releases for 6.x and 5.x, but no commits in the last year.
• Betting which has a 6.x release, and the last commit was 5 weeks ago, but there is an issue in the queue that says it doesn't work.
• Prediction Market no releases and no open bugs, active 28 weeks ago.
• Prediction Markets (I wrote this one) largely abandoned after the initial architecture of relying on other modules proved to be too brittle/easily broken.

I'm not really sure which of these is the best one to focus energy around. I can say that my strategy of relying on other contribs for as many features as possible was, unfortunately, too unstable to be useful in the future. The first three items seem worth investigating.

EDIT: New guy!

• Prediction game I haven't tried it yet. Maybe it's good?