Question: Functions Usage and Syntax?

[CrimsonFenrir]

In the "Configure Input" window you can bring up by right-clicking on a button in one of the controller configuration windows, I see there are three drop-down menus: User Variables, Operators, and Functions. I found the article on the wiki explaining input syntax, but it's lacking any information about the Functions. Does anyone have that information, or know where I can find it? I'd like to know what each Function does and see some example usages.