American money has always baffled me.
I never flattered myself to think that I was the only person to notice that all the bank notes look and feel the same, and this suspicion was confirmed when I spied the following article: http://www.csmonitor.com/2006/1207/p17s02-lign.html
Sometimes living in a litigious, politically correct, paranoid society has its benefits (apart from being generally humourous, that is).
I also have trouble with the coinage. For example, the 10c piece (or dime to those of us who are on the inside track) doesn't declare that it's worth 10c, you're just supposed to know. And I seem to accumulate much more schrapnel in my pocket than I did in Blighty. However, this might be a function of the sales tax which gets added to the price of the item in question only when you get to the till, generally leading to a distinctly un-round price. Gets me every time. Guaranteed.
And the gentleman on the $20 definitely needs a haircut.