I stopped by Tiffin on Devon this weekend, and much to my surprise (based on the feedback here) found something called "Kerala Chili Crab" on the menu. Not sure how authentic it is, but it was delicious! The dish consisted of shredded crabmeat served in a "light" (relative to the rogan josh we also ordered) but very flavorful coconut-based sauce. There were chilis (as well as black cardamom seeds, I think) mixed in with it all, but the spicyness was definitely tame compared to, say, a vindaloo curry.
I heartily recommend the dish, even at its higher-than-average price tag of $16.