Paying the bill or leaving a tip with cash, I generally try to fold something out of the bills. Here are some ‘doodles’ I did yesterday; the tilted dollar I believe has been done (I’ll can’t find the reference now), but the rest I haven’t seen. Using US currency as an origami medium is actually quite useful; the US dollar is made out of some of the best paper available, it is dimensionally very consistent, it doesn’t rip, and it is widely available.
The $2 bill is yes, still in circulation. You can get them at any bank, you just have to ask. They are great as tips, and folded, they are even more unique.
Very clever.. good going…