Up until I played Gen IV, my team almost always consisted of my overleveled starter, and 4/5 legendaries. Maybe an HM Slave. DERP.
I bought into a lot of the crazy RBY rumors (Mist Stone, Bill's Garden, Pikablu, Mew under the truck, etc).
I used to think this was a gladiator's helmet: http://i52.*******.com/6rrc6g.png
I also used to think that Fire was strong against absolutely EVERY type except for Water. I smartened up on that one once Gen II came out, though.
...And I know it doesn't do anything, but I STILL mash A/B after throwing a Pokeball. :V