The coolest magic trick I've witnessed was at a small club in Los Angeles, by a regular of the magic castle. He had me pick a card and without showing him the card, he had me rip the card into pieces and asked me to tightly close my fist. He said he was going to reconstruct the card. I stared at my hand, keeping the fist clenched and waiting for a misdirection. He simply tapped my fist and asked me to open my hand. There was the card, back together again, folded up with the creases -- as far as I could tell -- where the rips had been earlier. To this day I'm still unsure how it works. One of the coolest things I've ever seen.