Well, without putting too much on the line, I think it's safe to say that the Black Condor has the absolutely least plausible superhero origin ever!
To sum it up: Like some sort of avian Tarzan, he was raised by Condors as a young baby and by simply watching them, and really, really wanting to, he learned to fly.
Physics. Be. Damned.
Anyway, this incredible origin and many other awesome stories can be found in this week's first Free Comic - Crack Comics 01.
Ah. Crack Comics. I think I use that term to describe many of today's modern comics, only not in the way most of the publishers would be happy with.
As a nice second to the Black Condor, I offer the only hero who is slightly more surreal, and that of course is Doll Man.