I don't usually stray above a dhansak but last night I took a chance on a Jhul Naga curry.
It didn't kill me but it was way too hot and I was glad to supplement it with spoonfuls of other people's milder curries.
I googled the naga chilli this morning and it turns out to be one of the worlds hottest.
Here's a youtube vid of an Australian guy eating one. It's worth sticking with for at least the first few minutes. I did skip to the end after a while.