Nothing hilarious here, but I hear the plain old 360 controller is a solid bet. It works well with most emulators from what I hear. I have a Logitech Dual Action, which is basically a clone of a PS2 ...
I remember Project64 used some weird system like combinations of keys to give different analog tilts, e.g. shift + left arrow might be 50% tilt. So that certainly didn't require an analog controller.
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