Interested in data on what APIs HN users build against most for an APIs related project.<p>If I'm missing an API that you use, comment (preferably with a link to the API docs) and I'll add it.<p>Thanks!
I find some interesting API from Mashape.<p>This is my favorite: <a href="http://www.mashape.com/component/BarCodeGenerator" rel="nofollow">http://www.mashape.com/component/BarCodeGenerator</a>
Since you added PayPal, you might as well throw Braintree in there. It's pretty great. I've been happy using it for an app I'm working on. Oh, and Mailchimp's API, too. I have a feeling that this list is going to go on and on.<p><a href="http://www.braintreepaymentsolutions.com/gateway/api" rel="nofollow">http://www.braintreepaymentsolutions.com/gateway/api</a><p><a href="http://apidocs.mailchimp.com/" rel="nofollow">http://apidocs.mailchimp.com/</a>
YQL - It's a bit of an API of APIs (if one can say that) <a href="http://developer.yahoo.com/yql/" rel="nofollow">http://developer.yahoo.com/yql/</a><p>I made a Drupal frontend module for it here: <a href="http://drupal.org/project/yql" rel="nofollow">http://drupal.org/project/yql</a>
I've actually switched from google to bing maps recently. Finding it easier to use and having more useful returns. I'm actually beginning to write a gem wrapper if anyone agrees and wants to contribute :) <a href="http://xjst.in/fUtWeW" rel="nofollow">http://xjst.in/fUtWeW</a> /shamelessplug><p>But before that, twitter is most used for me.
i did a web app map mashup of foursquare, gowalla, brightkite, twitter all in one, check out :<p><a href="http://checkinmania.com" rel="nofollow">http://checkinmania.com</a>