You can check out code samples in a bunch of different languages here: http://www.robertpenner.com/easing/

Funny note: That site and code has been around since the early Actionscript 2 days, and I went to hunt it down as a reply to ledneb. It looks like easing.net might actually be by the same guy ;)

Agreed. This seems highly focused on web development, showing the CSS and jQuery function calls, but it could potentially be very useful for other things, like games, or animations in desktop applications.

This x100. Show the actual equations no it can be useful for many more things.