I have no idea why this shot-for-shot parody of Toaru Kagaku no Railgun's is cracking me up, but it is. Actually, now that I think about it, I think it's because of the shot-for-shot parodying of the opening.
What does A Certain Scientific Railgun have to do with trains? Not much. There are trains in the anime's world. But it's not a train show, you know. I'm sure you'll agree that while it makes no sense, it's really well done.
As for the video, when there is walking, trains move slow. Running? Trains are blazin'. Hugging? Well, the trains connect, of course. Hilarious. And hopefully some of that hilarity carries over when you watch the second video we have for you, which gives that same train treatment to K-On! too.
Japan, you're so silly.