Zocalo – Toolkit for Building Prediction Markets
http://zocalo.sourceforge.net/

Zocalo is a toolkit for building prediction markets, markets in securities that pay out depending on outcomes of future events. They provide estimates of the likelihood of specific outcomes that are more reliable than other sources of predictions. The Zocalo Project Lead is Chris Hibbert with thanks to CommerceNet for their support of Zocalo. This has been added to Prediction Markets Subject Tracer™ Information Blog.