From their site: Betfair is the world's leading online betting exchange, a concept it has pioneered. Driven by cutting-edge technology, Betfair enables punters to choose their own odds and bet against each other, even after an event has started. Betfair processes 5 million transactions a day and more than 300 bets a second. The Betfair Sports API allows developers to integrate with the Betfair Sports Exchange.
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Klabor.com company build their product klabor bee based on this Betfair API. Klabor bee gives command-line easy to use interface for communication with betfair datafeed.