*I know the Academy defines it as 40 minutes or longer, but I'm after "movie"-length movies here.
I'm pretty sure Vantage Point (2008) has to be in the mix, as it's the same events as viewed from 8 different witnesses. I'm not sure exactly how long the span is, it's been a while since I saw it, but I feel like the main body of the movie covers the same 10 or so minutes several times.
It's difficult to tell how long does it actually take to tell the story in the police office in The Usual Suspects.
It could actually take few minutes even if the fictitious stories told to police officer take much longer to picture in the movie with all the details.
We can find out if we clock only the speech of the hero as the narrator and scenes in the office.
Since time is a relative concept we would have to take that into consideration. The Chronicles of Narnia cover minutes of time on earth but years in the fantasy land of Narnia. The same would apply to the Wizard of Oz and Alice in Wonderland.
While this won't win, TimeCrimes is shorter than the actual movie. Even though it has a time travel component, it is about 30-45 minutes of the same events from multiple perspectives. The wiki link has spoilers.
I believe that the "real time" of "The 5,000 Fingers of Dr. T" is shorter than Run Lola Run.
This was a disaster of a movie by Dr. Seuss, where a boy falls asleep during piano practice in the first few minutes of the movie. Much of the movie is then a dream sequence, until he wakes at the very end.
It's been a long time since I've seen it, but I believe the awake/present time sequences total less than 20 minutes.
Waking Life takes place in (I think) 6 minutes of real time.