Fabrice Bellard's work is impressive, but I wouldn't call it heroic. I was thinking more like, the grumpy-guts who ensures the local homeless shelter is adequately stocked with food, clean bedding, and toiletries, day-in and day-out, even in the depths of winter. You're allowed to be vaguely misanthropic in your interpersonal relationships if you're doing something like that, at least in my book.

Again, the only non-fictional people I know who qualify, are actually really nice to people.