I've always had a little geek crush on Thomas Edison. I wouldn't say that I really refer to these folks as heroes, but I do like to buy biographies of real people who have done things that matter. We have a fair sized collection of these at various reading levels.

Helen Keller, I am sure was at least HG, and probably PG.

There are some athletes who are positive role models, but they seem to get overshadowed by the steroid abusers, dog killers, etc.