Let's see... I laugh at all the difficult trainers I beat in every game I play.
I wouldn't exactly call this stupid, but I FORCED myself to beat Colress and get the Master Ball. Then I traded it over to my Black game through a Pokemon to catch freakin' Tornadus in. Holy crap, that thing is a pain. I was going to use it for Azelf, but it doesn't roam, at least.