Faster than a speeding bullet and not nearing as powerful as a locomotive: no its not Superman but it is the Flash. The original version was a member of the Justice Society back in the Golden Age of comics and has been a mainstream superhero for many, many decades. Ever since the recreation of the character in Barry Allen for the Silver Age the Flash has pretty much been a fan favorite and featured in some of the greatest comic book stories and television cartoons in the companies history. One thing the character hasn't been featured in however is a feature length, big budget film. Mathematically speaking it is almost unheard of that this character has not been made into a film, especially the way that technology has advanced and the fact that DC movies of late (excluding TDK trilogy of course) have generally been negatively received by audiences. The Flash has pretty much been announced to co-star with a large group of superheroes in the upcoming Justice League movie in 2015, but a hero this complex and well-loved should have the well deserved privilege to star in his own adventure, at least before joining his fellow heroes.
Looking back on the hero's rich history of villains, one would easily be able to select an appropriate opponent for the Flash. Whether Captain Cold and his ice powers could
be an amazing spectacle with special effects, or the Mirror Master as an intelligent, deceptive villain. One nemesis that comes to mind, who would also pose the biggest threat to our hero would be Zoom. Having the exact powers of the Flash, and in some cases being faster, he could represent a perfect detection of the "anti-hero" being almost the opposite of the Flash.
Few actors have a comedic yet heroic charm needed for the role of Barry Allen or Wally West or essentially any of the past Flash's. Ryan Reynolds presents himself as the obvious first choice, having all of the necessary qualities rather inherently. I know, I know... He can't possibly play Flash after he just played Green Lantern only a couple years back, but that's what everyone said when Chris Evans was selected as Captain America, having played the Human Torch in Fantastic Four, just four years earlier. If the Justice League movie intends to create a new DC universe (similar to the films leading up to The Avengers film in a new cinematic Marvel universe) and if it intends to introduce new characters like the Flash in the film, then a new Green Lantern should be selected, to detach itself from having any relation to the recent film, freeing up Reynolds to become the Scarlet Speedster. Assuming this Man Of Steel movie is the first of DC's new cinematic universe, introducing key heroes like WonderWoman or the Flash will be tremendously difficult, especially because each have very complex and intriguing back stories; stories that shouldn't be rushed through a Justice League film. A successful plan would be to give each hero their own film, which would eventually tie into the future Justice League movie (similar to Marvel's plan, but perhaps spread out in two years instead of four).
Anyway you cut it, Flash is one of the most successful comic characters of all time, and the fact that it has taken nearly 60 years after his creation to realize making a multi-million dollar film starring him could be beneficial, is ridiculous. Still, no matter how they do it: splitting him into a solo movie or explaining it in the JL film, Flash will be interesting to see on the big screen, unfortunately 2015 is still a long ways down the road, even for the fastest man alive.