Shoudio is an amusing iOS application made to tag places with audio snippets. These can be anything a user imagines, and a lot of fun could be had with this. For example, integrating this into Geocaching could be a lot of fun, allowing things like audio hints to help Geocachers find the cache. However, the developers of Shoudio didn't want it limited to just one platform, so they released a Shoudio API to allow clients for other platforms, and fun mashups.
From billion dollar companies to the neighborhood coffee shops, merchants of all sizes are seeking new ways to offer secure and affordable mobile payments systems that expand their ability to conduct business. The PayPal API got its start this way, first with online auctions, then with thousands of websites and individuals. It's now one of over 150 payment APIs, many of which exist outside of traditional finance.