2. Donnie Darko

No disrespect to everything he's done after, but Jake Gyllenhaal's Donnie Darko remains one of his best to date. It features a much different performance than the characters Gyllenhaal would become later in life. It may not be the most groundbreaking performance the actor has ever given Hollywood, but it is the one that really set him on a path to be one of Hollywood's premiere names. Without it, there's no telling where the actor would be today. Plus, the movie itself still holds up.