When someone discovers something great. Then, someone else takes that and calls it his own. Suddenly, everyone knows that person #2 "discovered" it. Really annoying when you're person #1. I'm sure we've all been in this situation before!
Person #1: Hey dude, look at this new strategy i just found! It cuts lots of time off of my score!
Person #2: HEY EVERYONE I JUST FOUND THIS NEW TACTIC I CAN BEAT YOU ALL NOW!
Person #1: Dude, that's the Christopher Columbus Effect. You can't just take me work!