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.
Playing online has never felt so close to home, thanks to the Dolphin Emulator's letting you share games that used to be ...