If you mean system-wide hotkeys (key combinations that work regardless of what application is currently active), that's pretty much what my ActiveHotkeys
Caveat: Windows make it impossible to find out what program registered a particular hotkey. There just isn't a way to find this out. So ActiveHotkeys will tell you what system-wide hotkeys are registered, but not what apps they belong to.
(Oh, there's no way to print the list, sorry!)
However, if you want to know all the key combinations available within a particular application (e.g. Ctrl+N = New document in Word), than no, I don't think this can be done. There is no way to poll an application for all the key combinations it uses to trigger its functions.