Civil Disobedience Against Geithner?

Outraged over the "rampant elitism and corruption in our government" demonstrated by the appointment of Geithner to Treasury Secretary who is "almost certainly a tax cheat", WheresTheChange.blogspot.com decided to take action.

In there own words (http://wheresthechange.blogspot.com/2009/02/civil-disobedience.html):
"I intend to start practicing civil disobedience. In the case of Treasury Secretary Geithner, I am going to have a rubber stamp made that says "Tax Cheat!" in block letters. Every time I see a piece of paper currency with Geithner's signature on it, I am going to stamp over his name with my Tax Cheat stamp."

There is some question as to if this act is actually civil disobedience focusing on if the act of stamping US currency is actually illegal. Based on the comments it seems there is some support for the idea. They are even discussing where they can get the cheapest stamps the quickest.