a bit nerdy but I like this one so much :
Einstein covers his eyes and begins counting. While Heisenberg and Pascal run off and hide, Newton takes out some chalk and marks a square on the ground with a side length of exactly 1 meter, then sits down inside the square.
When Einstein is finished counting and sees Newton sitting on the ground, he yells, "Ha, I've found you, Newton!". Newton however replies, "No you haven't! You've found Pascal!
(ɹǝʇǝɯ ǝɹɐnbs ɹǝd uoʇʍǝu 1 = lɐɔsɐd 1)

)) It's a good one. Thank you.