I totally approve this thread, the inclusion of valid long-term profit for evil characters is key to a good role-playing experience. All too often short-term gain is woefully small when you look at the long-term benefits good choices get in exp/gold/items.
Mostly what I want to see is the inclusion of "smart" evil. Which lies, deceives and runs the long con instead of murdering all the kittens, as fun as that may be. It would be especially nice to be able to corrupt my companions, it was always a high point to bring the goody-two shoes down and destroy their moral highground.