Eating crabs (or how to make a big mess for some very small pieces of meat)

A typical San Franciscan experience is eating crabs (if you think that you are reading the wrong word, I mean exactly those small sea animals with claws and several legs; famous crabs include the honorable Eugene H. Krabs). Amazingly a 1.5 pound crab (750 grams) might have 150 grams of meat and generate 2 kg. of refuse after you eat.
According to well versed sources you should use a mallet, and not the nutcrackers I used. I guess that way I would have needed a complete shower, instead of only washing my clothes.
Anyway, it is a fun experience, not so much for the food, but... well, for the fun.