I like paper best, though admittedly I think rock is the safest option as most people go for rock or scissors on instinct so you've either got a draw or a win. That's the first move though - I've found when it goes to second round, people think more carefully about their choice.
Besides, I'm a writer. How can I not vote for paper?
According to all known laws of aviation, there is no way a bee should be able to fly. Its wings are too small to get its fat little body off the ground. — The Bee Movie