You did say "stupid" trick, so here goes.. :)
When you twiddle your thumbs, one hand's thumb goes clockwise, and the other goes counter-clockwise, correct? Well, I'm just so darn stupidly talented, that I can do both clockwise or both counter-clockwise. And no cheating like my husband tries, with the thumbs not going over each other.
Oh, I can even occasionally walk and chew gum at the same time. Ok, rarely.. ;-)
You did say stupid, so this qualifies!