Determine a person preffered hand without asking..
This is rather silly, and is pretty obvious. I was working last night, but trying not to think about so I started looking around, I figured out I have the longest hair in my department, I found out that not all the guys carry wallets only a few but still not all, then something hit, 'hey everyone who has a wallet carries it either on the left or right side, this probably corresponds with which hand they write with' so I started asking people in specific if they wrote with their left or right hand depending on which pocket i saw their wallet in. I asked three people, and my theory was proven amoung the three lol. kinda corny? WHO ASKED YOU!! lol ...talking to myself. I 'm gunna go insane.