The 21-Second Excitation - S4-E8
Corrected entry: Sheldon steals the 35mm movie canisters and 2 exterior metal cases for "Raiders Of The Lost Ark" so that they supposedly could see it at a later date. We then see Sheldon running with the movie canisters and cases. That would not even be remotely possible as the 2 sets of film weigh approximately 140-160 pounds. Each individual reel (of which there would be a total of 4) has a weight of somewhere between 30 and 35 pounds including the film and individual canister. If you add in the weight of just 2 canisters plus the carrying cases they come in, that's well beyond Sheldon's carrying capacity.
Correction: I worked with 35mm for 10 years. Each case weighed about 35 lbs for 3 reels.