Sarah made these incredibly handy interactive code reference... thingers.
The idea is perfect. I'm in this position regularly. I know what I have (i.e. an array or an object). I know what I want to do with it (i.e. get an array of all the keys in my object). But I forget the actual method name. These thingers guide you to the right method by letting you tell it what you got and what you wanna do.