Not exactly deliciousness to write home about, but there is soft-shell crab featured on the a volonte menu at Odaki Sushi, if you want to totally pig out on it. It's simply battered and fried and sliced into 5 pieces with a salty dipping sauce (I think something like broth, IIRC).
Odaki Restaurant Japonais
3977 Boul Saint-Laurent, Montreal, QC H2W1Y4, CA
I was at Milos a couple of years ago for my birthday. Their softshell crab was one of the best I ever had. I can't recall the price... alls I remember is it was quite expensive (problem with many birthdays...memory starts to ebb) but worth every penny.
We usually get a few as table appetizers when eating in chinatown at Beijing. Not extraordinary, but very tasty indeed.