Yeah, I was pretty bored earlier and decided to see how many superheroes I could name. I know, this confirms many a suspicion that I am a dork :P
the Atom
Aquaman
Apache Chief
Angel
Batman
Birdman
Birdboy
the Batgirl
Big Barda
Black Canary
Black Vulcan
Booster Gold
the Beast
Colossus
Captain America
Cyborg
Cyclops
Dove
Dare Devil
Doctor Fate
Elongated Man
El Dorado
the Flash
Firestar
the Flame
Firestorm
Green Lantern
Green Arrow
Gambit
Hawkgirl
Hawkman
Huntress
Hawk
Iceman
Icemaiden
the Invisible Woman
Jayna
Jubilee
Jean Grey
J'onn (the Martian)
Kilowog (the Green Lantern Corps)
Katma (the Green Lantern Corps)
Kitty Pryde
Metamorpho
Miss Marvel
Night Wing (Terry McGinnis)
Night crawler
Orion
Professor Charles Xavier
the Question
Rogue
Robin
Superman
Supergirl
Stretch
Stargirl
Storm
Scott Free
Space Ghost
Steel
Spiderman
Shining Knight
Samurai
the Swat Kats
the Thing
Vixen
Vigilante
Wolverine
Wonder Woman
Wonder girl
Wildcat
Warhawk
Zan
Zatanna
Zandor and the Herculoids
So how many/who have I forgotten??