I did once throw a strap of US$1s in the washer on gentle cycle for a few minutes with a couple drops of laundry detergent. Then I pulled them out, ironed them and stamped them with Where's George. It was a really ratty strap from a small town BofA branch.
" You ever just make a big mess of bank notes on accident?" Yes, I call it my foreign currency collection. When I started collecting currency I didn't like the sleeves the currency came in so removed them from the sleeves along w/ the Pick numbers. Now, I've got a lot of foreign currency that needs to be cataloged. Had I left them in the original sleeves it would've been an easy task.
"Wait whaaaaaa, you put money in the washhhh?" Years ago, I dated a bank teller who would give me interesting currency she would discover while at work. When I did my laundry I put the old dirty currency in khaki pants pockets then iron the currency (and the pants) after they were dry. Looked good to me.
It actually flattens the intaglio printing a bit. But they work fine for WheresGeorge... and I did get a couple hits 3, 4 even 5 years later from the "ratty" bills.