Mary Sue Evaluator
We writers are up to our eyeballs in Mary Sue litmus tests. Most of them try to list every possible characteristic a character could have that some Mary Sue has had in their particular fandom. Personally, I think they're missing the main point. Sue-ness transcends canon and genre. The real problem is not what color hair a character has, how many exotic pets are involved, nor even the quantity and quality of purported flaws. It's whether the character was written to serve the story or the story was written to showcase the character. When a story amounts to "look at this really cool character I made", that character is most likely a Mary Sue.
A big warning sign is whether the canon characters are merely extras. If the questionable character is not just a guest star but the star, the center of a story that's all about her, there's a big problem and its name is Mary Sue. In a lot of cases, it's the "I know it when I see it" syndrome: we can't agree on what belongs in a litmus test, but when we see some story that is just the author's wish-fulfillment, we know we have a Mary Sue on our hands.
So here's a slightly different Mary Sue test, designed from scratch. Instead of characteristic lists, it's made up of questions meant to identify characters that deviate from the canon norm, whatever "normal" might be for that canon. While it was written for Hogan's Heroes, it should work just as well for, say, Neon Genesis: Evangelion. The critical question to keep in mind is whether the character being examined fits in with, or stands out from, the canon characters and world.
No series of questions can reliably identify every Mary Sue. However, while the race may not be always to the swift nor the battle to the strong, that's the way to bet.* So while exceptions do exist, the odds are low that your character is one of them. Also, no one answer will proclaim that character a Mary Sue. However, the odds are if a character fits more than a couple of those characteristics, it is most likely not a good character and needs a re-think, Sue or not.
When you're ready to start answering questions (it doesn't take very long, they're all yes/no) supply your character's name and sex below (so the question wording comes out right) and press the button.
Notes for the politically correct: Yes, there are Gary Stus out there. For reasons that you're welcome to fill up my forums debating, they're far rarer than Mary Sues. And yes, there are characters who are not definably male or female. Since the only difference it makes is the pronoun used in these questions, feel welcome to pick either, as the English language is sadly lacking in a neuter alternative.
* Damon Runyan