Man, I love this gamepad...
http://www.saitekusa.com/usa/prod/p880.htm
IMHO, the best possible solution for any emu. Genesis-like buttons for the pressing-buttons (hmm.. that was horribly worded), two triggers, 8-way d-pad, two analog sticks (that also work as a button like in modern game systems) and a "Digital" button that switches the left stick and the d-pad. Nice, eh? Not to mention it comes with software to program what it does (haven't looked at that yet... but its probably gonna be REALLY awexome)