macosxhints - An OS X keyboard shortcut reference
Well, probably not all of them. A complete collection is probably impossible, since they vary between machines and OS versions. One imagines an immense grid in several dimensions ...
The comments reference other collections, including Apple's. I've printed them into one big pile in my desk -- useful for when the Mac isn't working.
A psychoanalyst could make much of the Mac keyboard fetish -- especially since the Mac was born of a the mouse world. Single button mouse, one trillion keyboard shortcuts ... hmmm. Compensation perhaps?