Something you never think about normally, but I wonder if they put an earth quake proof base on the SOL? Would make a real mess if it fell plus be a really bad symbol for the US. I'd also hate to think about the repairs / scrapage of the SOL given the height the top would fall as it's one of those irreplaceable icons.
Remember long time ago I bought something from a store and then got my changes back and then notice my wallet stink the next time I took it out of my pocket. I don't know what kind of smell that was but it was from one of the dollar bill in the wallet. And I have to throw it away and air out my wallet a little. This warning would've been helpful.
If you got a chance always wash your hands after touching money. You never know where these money travel through before it got into your hand.