Space Jetpacks, Pt. 2
The movie: Stone is sent spinning into outer space after the debris hits the Explorer. Kowalsky uses his MMU to find her and bring her back to the shuttle.
Real life: During spacewalks, astronauts are required to wear a SAFER (Simplified Aid for EVA Rescue), which is a more basic version of the MMU. It is intended for emergencies only, and Stone would not have been repairing the Hubble without one. She may not have been able to get back all the way back to the Explorer with it, but it would have been her first line of defense against the prospect of drifting off forever.