First Appearance: Marvel Preview #7 (1976)
Abilities: None except for his quantum bands which give him immense control over quantum energy. He uses the bands to create quantum constructs similar to what Green Lantern might do with his ring (hmmmm, wonder where Marvel got that idea?).  More recently though, Quasar has become a living Quantum energy form.  He can also fly in space and shoot energy blasts.
Chances he's in the movie: 50%.
Lowdown: After graduation from S.H.I.E.L.D. Academy, Wendall Vaughn was rejected from field duty for not having a "killer instinct." While a security guard at a research facility where the quantum bands are being tested, he comes under attack from AIM scientists (don't ask). Putting on the bands to protect himself he discovers their true powers and saves the day.  It turns out the bands worked just for him because of his relaxed personality. After a few adventures as Marvel Boy, he becomes the hero Quasar and discovers that the bands were intended to be worn by the "Protector of the Universe." He then takes on that responsibility and eventually joins a super-powered version of the Guardians which include Nova and the Silver Surfer, among others. If Marvel decides to include him in the movie, Quasar would be another Earth-born hero for the team and his Captain America-like personality would make him the most relatable member of the group.  Considering the intense CG effects needed to create his powers, he could also be saved for a sequel.