Space Jetpacks 4eva
The movie: Matt Kowalsky (George Clooney) dicks around with his awesome space jetpack for the entire opening of the movie, and then uses it to retrieve Ryan Stone (Sandra Bullock) post-disaster. After that, he putters them both along to the ISS.
Real life: Space jetpacks really do exist! They are called MMUs (Manned Maneuvering Units), and they are every bit as awesome as they sound. Even so, they are not practical for most missions and were retired almost 30 years ago.
They are also not a replacement for a freaking spaceship — duh. Space is big! You can't just backpack around it the way you backpack around Europe. It would be difficult for Kowalsky to retrieve Stone, let alone use his jetpack's nitrogen farts to reach another spacecraft. Especially since he had already used a lot of the juice up before the accident, that beautiful idiot.