The KISSmetrics Node.js SDK by Gabriel Lesperance allows API interaction to implement data analytics into marketing applications. Resources include configuration, JSON package, and usage. Source code available at https://github.com/glesperance/node-kissmetrics/blob/master/lib/kissmetrics.js
Location-sharing service Foursquare was down most of Monday, apparently due to a database issue. No Foursquare website or apps were available. And with the API also down, third party applications were helpless. Yet, it's a good reminder to developers to plan for downtime and to providers to have communications in place to let others know about your service's issues when they arise.