When I came home from Portland last week, I noticed some red and blue writing on one of my dollar bills when I took it out of my pocket.
So I went to WheresGeorge.com, entered the bill along with its current postition (Waterford, VA) and found that it had recently been added in Beaverton, OR -- not a short distance away, but easily explainable given that I just came back from Portland).
After poking around a bit, I became hooked and went about figuring out how to more actively participate. First off I had to get my own stamps so I could stamp my bills. Unfortunately, WheresGeorge.com doesn't sell stamps (according to Wikipedia, the secret service investigated and told them it was illegal because it amounted to advertising on money). Poking around a bit (googling "WheresGeorge Rubber Stamp") I found several places, selected Stamp-Connection.com and ordered my stamps. They came in yesterday and I'm off and running, entering all of the cash lying about.
I am concerned a bit about dealing with the cash that I get during the day... What if I spend it before I enter it... Should I log it immediately... Should I only spend marked cash and save the unmarked cash for marking when I'm home... Gosh... It's like blogging & watching readership stats... It's addictive..
Of course, for those privacy weenies out there, I do realize that I'm giving up some of the anonymous properties of my cash transactions... but it's fun!