Leonardo DiCaprio and Cillian Murphy as Cobb and Robert Fischer in "Inception" (2010) directed by Christopher Nolan
"I've already referenced Inception, which other reviewers have done already, in terms of the technical wizardry, so let's go with a slightly less obvious but just as relevant reference with Avatar. 
You'll remember that, when he wasn't giant and blue, Sam Worthington was an otherwise disabled, regular human caught up in affairs that were far larger than him. That's perhaps the key to understanding Source Code right there.
Still of Keira Knightley and Sam Worthington as Joanna and Michael Reed in Last Night (2010) directed by Massy Tadjedin
Jake Gyllenhaal and Anne Hathaway as Jamie Randall and Maggie Murdock in "Love and other drugs" (2010) directed by Edward Zwick
Jennifer Aniston and Jake Gyllenhaal as Justine Last and Holden Worther in "The Good Girl" (2002) directed by Miguel ArtetaJake Gyllenhaal, an actor I personally have only seen in a handful of movies (The Good Girl, an earlier effort most people might have forgotten about by now, and last year's Prince of Persia, basically), is in much the same boat as Worthington.
The audience doesn't find out Jake's particular circumstances until very late in the movie, and I won't tell you all the details here, but it's a good link to make, since the rest of his journey is equally similar.
The Social Index: Jake Gyllenhaal is an actor Hollywood has repeatedly turned to when it's got a project that seems like a tough sell, and he seems to have become perfectly comfortable in that role. 
In a way, he's establishing a career that's not all that different from a Leonardo DiCaprio, and so that makes the parallels with "Inception" all the more appropriate. While Duncan Jones is establishing a career that resembles Christopher Nolan's, for now it's Gyllenhaal who will drive the interest for "Source Code". Source: www.examiner.com
