I built PriceArb based on noticing how emotional live prediction markets (Kalshi/Polymarket) can get and reprice during NFL games. PriceArb compares the current game state (score, time left, possession) and team records against similar historical games to highlight spots where prices under or overpriced vs. hundreds of historical comparisons. It’s meant for short-term trading (fade extremes, exit quickly), not as a buy-and-hold 'outcome predictor' — I’ve seen plenty of cases where a trade idea works even though the final outcome didn’t. NFL only for now; two contracts from all sport categories will be free forever.