This is a cool site which is designed to help bikers recognize each other. The site operator will send you two free bumperstickers which declare that you are 'biker friendly', i.e. willing to bikes a little extra room on the street and help other bikers if they're in trouble and you aren't in a hurry.
Its a neat pledge, and totally free. I don't own a cage (why do you think I'm riding a '96 GS500? I'm poor!) but got a couple of these and stuck them in the back window of the car I occasionally borrow from my parents. The site owner ships them nationwide, but seems to get them out within a week or two. If we could get a bunch of riders from Chicago to request these it might make life easier for all of us.
I've only been riding for a year, but I consider biker traditions to be of the utmost importance. I wave to everyone on two wheels, and extending a bit of courtesy to fellow riders is the least we can do. I've made my share of jokes about Harleys, but when I crashed last summer it was a newbie Harley rider and his wife who stopped to make sure I was ok. We gotta look out for each other regardless of bike make or what gear a rider is wearing.