We seem to be in a golden age for superhero movies, not just in terms of comic book based ones but more independent versions as well, starting, coincidentally(?) the same year that X-Men came out. To wit:
1. The Specials (2000): Mainly heroes talking in their headquarters. Perhaps the weakest of this bunch but at least an attempt to do something a bit different with a superhero movie.
2. Citizen Toxie: The Toxic Avenger IV (2000): While there have been comic books based on the Toxic Avenger, he started as a movie character first. This installment has fun with the old chestnut of the hero encountering an evil universe version of his home world. Typical over the top Troma silliness ensues.
3. Superguy: Beneath the Cape (2000): Mock documentary of a flawed hero weith Superman-like powers.
4. Unbreakable (2000): By far the best of the superhero movies to come out in 2000 (including X-Men): A mysterious man manoeuvres a guy who can’t be harmed and who wants to live a low key life into become a hero.
5. Ultrachrist! (2003): Jesus returns to Earth and decides to become a superhero to help get his message across.
6. Sidekick (2005): A social outcast finds a guy with powers and tries to train him into becoming a superhero so he can be his would-be hero’s sidekick.
7. Special (2006): Not to be confused with The Specials above, a parking attendant is given experimental medication that deludes him into believing he has powers.
8. Paper Man (2009): A frustrated writer with a superhero for an imaginary friend has trouble connecting with real people; he befriends a young woman with similar issues. Perhaps not the most complementary film to people who enjoy superhero entertainment, but still a decent low key drama.
9. Defendor (2009): A man with developmental disabilities but with a certain level of strategy understanding decides to become a low rent Batman style hero and take on the underworld.
10. Super (2010): A man whose wife leaves him for her drug dealer, inspired by a young woman who works at a comic shop, decides to become a costumed vigilante, resulting in a gradual escalation of violence and its consequences.
Of the above, four of these stand out as exceptional: Unbreakable, Sidekick, Defendor, and Super. All but Unbreakable are partly comedies but even those get serious when the plot calls for it. All four have a fascinating main character who draws you into their world.
A note about Kick-Ass: In many ways it has a similar independent feel to it. However, it is based on a comic that had just started at the time work on the movie began, hence its exclusion.