Before I left the USA, I would special order stacks of $2 bills by the thousands and use them for tipping (particularly at bars) and to hand them to friends and

Before I left the USA, I would special order stacks of $2 bills by the thousands and use them for tipping (particularly at bars) and to hand them to friends and acquaintances. It's crazy how much more people appreciate being given a $2 bill vs two singles. People save them and keep them as lucky charms. I got the best service when know as the guy who tipped in twos.