The Battle.net PHP SDK by Oleg Kachinsky allows developers to integrate the Battle.net APIs into their PHP applications. Basic usage examples are provided in the documentation. This SDK is provided under the MIT license.
There's no doubt that Wikipedia is a giant store of information. And yes, they have an API, but the data isn't exactly structured. But that didn't stop Jim Blackler, who created Quizipedia, a fun game based off of Wikipedia entries.
Last week I had the pleasure of attending the O’Reilly Strata Conference in New York City, and sat in on a very important keynote from Drew Conway and Jake Porway about their project, Data Without Borders.
Data Without Borders is looking to match non-profits in need of data analysis with freelance and pro bono data scientists who can work to help them with data collection, analysis, visualization, or provide decision support.