Growing up in Malaysia, I have developed an unnatural ability to eat things that can normally destroy a human being.
I can say I've eaten pretty much all kinds of peppers (including thai peppers, which I pretty much eat regularly and the dreaded Red Savina, which is probably the most potent pepper I've eaten).
My grandmother, however, is a legend when it comes to pepper eating. She would eat nothing but a bag of Red Thai Peppers like candy while playing majong.
http://en.wikipedia.org/wiki/Thai_pepper