Zach and Dr. Brennan from "Bones" are both Aspies, though only Zach actually has the diagnosis. There's been lots of talk (by the actors) about Dr. Brennan and how she would be diagnosed if the producers let her be--only they don't want to write a show that's about autism. (Somehow, if the main character has that diagnosis, then it's automatically a show about autism. Color me puzzled.) I've heard that Sheldon from "Big Bang Theory" is autistic, but I haven't seen that show.

There are a few books that specifically have an autistic character. "The Speed of Dark" is a near-future sci-fi book with an autistic main character; "The Curious Incident of the Dog in the Night-Time" has a main character who's got Asperger's (but a pretty stereotypical case). Neither one is half-bad (though "The Speed of Dark" will really depress you).

Dean Koontz's "By the Light of the Moon" has an autistic character in it; like the other two main characters, the guy ends up with superpowers. The author handles it in a generally indifferent way, though Koontz has a bad habit of turning his disabled characters "inspirational" through the assumption that disability=bad.

Then there's the bad stuff. "The Secret of Susan", from Baby-Sitters Club, has an autistic savant character who is pretty badly miswritten until she goes to an institution because that's somehow better for her. And Diane Duane's "A Wizard Alone" has a supposedly autistic Darryl McAllister, but the actual disorder is really more of a dissociative disorder, having little in common with autism; and the magic cure doesn't help. Makes me sad, because she usually does her research really well.

...that Parker from the tv series Leverage has at least a mild form of autism, and I know that there's at least one possibly autistic person on the show Alphas. I can't fully verify the latter, as I don't watch the show, but from what I've seen of the character, it makes sense.

Namely that it's so hard to figure out how to write them well, given the huge variety in people suffering with it (though it's certainly not hard to identify when they're being written WRONG).

If you've got some time to read, I remember Diane Duane doing autism fairly well in one of her Young Wizard's series, "A Wizard Alone".

(And if you need some personal accounts of what it's like to have very mild autism/AS, I'm more than willing to offer some, Lab.)

Can I have a link, please? What fandom was it in? Might be interesting.

Anyway, I don't really know. I know there are some canons that have definite mental disability.

If you need something to work with, I suggest you start with a Bioware continuum, because they both do a great job of writing disabled characters. I mean, there's Sandal from Dragon Age, who is really charming in his own way while being massively disabled, and then there's also David Archer from Mass Effect 2's Overlord DLC, a savant who... let's just say that the end of the DLC is really sad because he's involved in something. Oh, and the ME continuum also has Gillian Grayson, though she only appears in the novels for some reason.

...Since in fiction, it's... somewhat ambiguous.

There's a page on TVTtropes about it (but be warned, this site has a tendency to pull you in): http://tvtropes.org/pmwiki/pmwiki.php/Main/AmbiguousDisorder?from=Main.AmbiguouslyAutistic