a) Wave back.
b) Give him your lunch money.
c) Give him an obscene gesture and

at a blistering 45 mph (72 kph) away.
d) All of the above.
e) Beat up the biker and take his/her ride.
An email got me thinking. Why don't we scooterist wave back?
My reply is here:
http://2smallerwheels.blogspot.com/2...-scooters.html
Comment, send love/hate mail. whatever.