Who says it has to be heroic? Destiny can choose even the most self-iterested carnage-lover to become the reluctant savior of mankind.
The thing is, evil doesn't nessecarily mean beating-up-the-elderly evil. It could just be selfish-and-conniving evil, or run of the mill uncrontrolable-violent-urge evil, or power-trip-mad evil.
In fact, evil can be downright a blast for some one-shot campaigns (oh, my players had such *fun* killing Elminster!

)
As long as you disassociate evil from True Blackest of Heart Deviltry, you can be alright. Just because your chaotic evil doesn't mean you want to eat *every* baby that comes along. It just may mean that you're not above doing it, if they, y'know, get in the way. They were askin' for it.
Evil characters can still have desires and wants that mediate their wickedness. Like so:
DM: Tonight's quest is to save the kidnapped princess
EvilDude: Pheh. Why would I want to do something like that?
PaladinDude: Because if you don't serve your community like a good prisoner, this sword is going in places that are usually exit-only.
Evil can be alright, as long as you don't get too serious about it. Once you start thinking of what an evil character is *really* capable of doing, you start to loose a desire to play them, becuase you don't feel comfortable with what your character would do....and then, that's when they get caught by the town guard.