A few years back (about 2007) I ran a Marvel Superheroes game with randomly generated heroes. The concept had been somewhat similar to what Kick Ass would be: Street level, more realistic heroes... inspired by Marvel's New Universe titles from the '80s. The characters all lived in a fictionalized version of Pittsburgh, and one day while at the mall, they tried to intervene in a robbery... before they could be murdered by the baddies, a legitimate superhero showed up and saved them, although he was shot and mortally wounded. This "alien" superhero's blood acted as a powerful mutagen that bestowed on the PCs unexplainable powers.
The game was fun, a human plant, a demon offspring, a homicidal robot, a rather personable megalomaniac that invaded the city. The TSR rules proved a bit limiting for lower powered heroes and we tried a few other rules systems including Mutants & Masterminds and Necessary Evil... finally the Savage Worlds Superpowers Companion allowed us to properly realize the concepts.
Messing around with HeroLab I came up with these sketches of two of the PCs:
Brad Sterling - Youth Outreach Coordinator, Mt. Ararat Baptist Church. When
Brad, a former army Ranger, is exposed to an other-worldly
mutagen, he gains powers far beyond those of mortal man. He takes up the mantle
of: Christian Soldier!
Scott Lawson - Legal Aide Clerk, Metropolitan County Courts. After stopping a robbery, Scott is chosen by a dying alien to become the City's champion of justice, and manifests the ability to become an animate plant. He is Overgrowth!