Travel reservation site Expedia starting working on its Expedia API back in 2009, according to the changelog. It has three APIs, covering hotels, flights and cars. Don't be shy. Expedia has been expecting you. The Expedia developer site has all the warmth and care of a fine bed and breakfast. They clearly want to invite you in, make you comfortable, and get your development project of the ground. Though they do have a couple hoops to jump through, as well.
Cabforce; advanced booking service for taxis, minibuses and executive cars; just announced its Cabforce Taxi Content Hub. The new offering provides the Taxi API that developers can integrate with third party travel applications to retrieve routes and rates as well as book flat-rate rides. The API grants full access to Cabforce's platform which organizes a fleet of more than 10,000 cabs and private cars throughout Europe and New York.