Black Lagoon. One of my all-time favourite anime besides Initial D, about a group of pirates from Roanapur (A fictional city overrun with any kind of crime you can think of) who pick up a Japanese businessman named "Rock" and pretty much corrupt him.
Just an absolute amazing show. It's hilarious, entertaining, action filled, great dialogue, pretty good character development, and over all. Its just so hilarious. Its like the writers where given a blank piece of paper and were given the orders "Okay guys, go crazy. Just make it good, other than that. Go crazy". cx