My absolute favorite is Tapatio but I really do like most hot sauces. I eat the Taco Bell fire sauce right from the package lol.
Very rarely do I run across something "too spicy". My dad makes a sausage dish where the sausages have to slow cook in about 12 different hot sauces. If that doesn't curl your toe hair I don't know what will! I grew up on spicy food so nothing bothers me now :p