Talking of coins lying around, we used to have stacks of all sorts of foreign ones accumulated over the years, including pre Euro e.g. Austrian schillings, etc. Also a few out of date UK coins.
Dh recently found that a co. called Fourex.com has machines in various places inc. at a couple of big London railway stations, where you can feed them in (notes too inc. small ones the banks won't exchange) and get something back. They do tell you on the website the. rate for each of umpteen currencies.
Quite apart from making space in drawers and cupboards, Dh came back with over £90 from ours!
Recently did the same for a dd, who had sundry pots of coins lying about - £51 odd!