It's not going to please the technical purists, but if you're looking for a plugin that will enable you to add loudness to your mixes with just a single control, Dotec-Audio's DeeMax could help.
Equipped with a big, chunky slider that looks like it's come out of Dr Emmett Brown's DeLorean, you're promised "fat saturation" as you crank it up, and the plugin is designed to be used both in the studio and in live situations.
There's a demo for you to try, and DeeMax is available at the reduced price of $29 (as opposed to $49) until the end of the year (it's available in 32/64-bit VST formats for PC and Mac). Find out more on the Dotec-Audio website.