Certain species of crocodile can get HUGE! The biggest crocidilian in the world is the saltwater croc... it can get up to lengths of 15-20 ft (though it's rare). The longest recorded, was supposedly 30 feet in length.

Wouldn't wanna meet one of those in the streets of New Orleans...

http://www.flmnh.ufl.edu/natsci/herp...s/csp_cpor.htm