A long, looooong time ago, one of my first experiences reading a video game magazine was learning about the shortcut in Super Mario Bros. 2 where you can bypass pretty much all of level 6-3 by going under the wall in the quicksand. When I first read that, it blew my mind and had to rush home and try it out for myself, because I had always done that level the hard way.
Now I'm nostalgic for whatever magazine had that secret- I'm sure many around that time period had it, but anyone know of some places to start? I'm assuming it was either GamePro or EGM (I live in the U.S.) but who knows.