"Journal Entry #57: Spin class sucks."
During World War I, the German army outfitted its troops with "pedal-operated" generators, i.e. bicycles with a bigger dynamo instead of tires. On these tandem bicycles, two German soldiers would sit together intimately, pedaling for power and going nowhere -- like the least romantic French holiday ever. When stumbling upon these bicycle frames, British soldiers marveled at them like it was some weird alien tech. As one officer's letter read: "It is exactly like a tandem bicycle without its wheels. I am not sure if it ever was a bicycle." Leave it to the Germans to create military equipment that can also induce philosophical crises.
"Is the "I" for World War ONE or World War EYE?"
The Allied forces speculated that these bikes were mainly used to power the lighting rigs in the German trenches. So the lights going out in a German trench could have two causes: either you were going to have to change a bulb, or write a letter to someone's widow. However, their green energy initiative was deemed successful enough that the Germans ported the system over to round two. Communication networks were more important than ever during World War II, so German troops were again given these tandem bicycles to power their outposts' radio systems in case their batteries or gasoline ran out. It's a shame that there isn't a single WWII movie that has a scene where the stoic U.S. sniper gets distracted during battle because he just spotted two red-faced Bavarians going to town on an exercise bike.