This quote from Thoreau, written nearly 200 years ago, was probably one of the most influential on my young mind when I first read it. In fact, I would say it eventually led me to the Exit and Build strategy and the idea that we can "vote" with our actions, not just with a piece of paper (or the press of a button).
"Cast your whole vote, not a strip of paper merely, but your whole influence. A minority is powerless while it conforms to the majority; it is not even a minority then; but it is irresistible when it clogs by its whole weight. If the alternative is to keep all just men in prison, or give up war and slavery, the State will not hesitate which to choose. If a thousand men were not to pay their tax-bills this year, that would not be a violent and bloody measure, as it would be to pay them, and enable the State to commit violence and shed innocent blood. This is, in fact, the definition of a peaceable revolution, if any such is possible."