I was final able to go to a Austin Homegrown API meetup Wednesday night. The most pleasant event was my car not being towed from the Wright Bros. Brew and Brew's parking lot even though I didn't know to get a validation pass.
Keith Casey spoke about an intriguing 100 line demonstration program he wrote using the Uber API to automatically check your calendar and arrange an Uber ride at the time needed, taking in account the current traffic conditions. More at his Future of Transportation post.
Dustin Blanchard of CarServ showed his work using the Edmunds API. I was surprised about how much info is available for free. Edmunds allows low volumes of queries for free once you have a developer key.
Both speakers related that the API providers were eager for them to use their service.