I’m starting to use this site again!
let’s start off with a simple one: HTML5 Compass.
Just an FYI its mostly only partially supported (http://caniuse.com/#search=deviceorientation).
Super simps, just include the script below: and you should be up and running with the compass. NOTE: just remove the jquery closure if you arent using it.
You might want to think about using something like modernizr to check as well. Also, you might want to think about wrapping it in a closure so you fire this after the window loads.