[rachelbythebay]

I'm using it on my scanner site. Logging in lets you use a few more features that otherwise would be unavailable. It wasn't terribly difficult to add to my stack. The hardest part was finding and integrating a reasonable JSON interpreter to deal with the return. I wound up using a library called jansson.

http://scanner.rachelbythebay.com/main - hit the cog/gear link on a call and you'll see the login button. Notice that once you're logged in, the "ops" popup drops the button and adds a few more features without you having to do anything else.