i don't know if i've read any like it. i've seen books that seem to be selling themselves as doing the same thing, using humor to teach, like "Sun Tzu was a Sissy" or "the No Asshole Rule", but a) i haven't read these and b) i think both those books deal with management techniques and not general philosophies. "hilarious-inspirational" is a weird word choice, but you're right, i don't know if any other books do what secrets of the superoptimist does.
if anyone who hasn't read superoptimist has no idea what we're talking about
: the book's website has a bunch of writing that didn't make it into the book but serves as a good example of the authors' style. here's a link:
http://www.superoptimist.com/archive...eady-been-done