I believe people should only deface money if they have a perfectly good reason to do so. Then again, even if they didn’t, it’s their money anyway. An example of a ‘good reason’ would be the one Aslan Malik from Berlin, Germany had when he set out to deface a series of US currency by turning the presidents into some of the world’s most renowned superheroes.
Money never looked this cool. Check out the entire series that Aslan did after the break.