Google has been running an internal prediction market – Gleangen, and Astral Codex Ten has a great write up on the topic.
This is the second iteration of such a market (the first was called Prophit).
Google claims that anyone can now build a prediction market on Google Cloud.
Prediction markets are fascinating as a tool but have struggled to get really big and more importantly to solve the three key issues (real money, easy to use, easy to create own markets).
Metaculus is a community dedicated to making accurate predictions (they have a great resource page) as is Manifold. Neither use real money.
Kalshi is a new startup ($30m of funding) that is trying to make events into an asset class via a real money prediction market. As is Futuur.
Polymarket, the biggest such market in the US, was recently fined and forced to shut down in the US (it remains open elsewhere).
