As Jarred mentioned the list of fish that fit that catagory is a quite long one, and each species and sub-species, has its own "Bad Boys" .
Which ones you keep or are able to keep depends on a lot of variables, such as what size tank do you have or are you willing to buy to house these guys?
Do you lean toward smaller fish that do best in groups, or would you be happy with just a single fish or two.
In my experience the chiclid species, simply because of the vast number of different species in that family maybe, holds the most options for you to choose from.