I went do do shopping today with my wife (yes I know...). Anyway, I was there and we did not have any change for the shopping cart release mechanism (ALDI and other supermarkets use a mechanical release to unchain the cart). We needed a quarter ... It really blew as I had to find a gas station to change a dollar... Here comes COIN CART. This simple coin-shaped key fits in your keychain and is bound to make your life (or your wife's life) much easier since you'll never need to remember to have a quarter, and, as an extra bonus, it holds your car keys out ready for when you need them to open the trunk (women will appreciate this since they never have pockets!)
Print in ABS and enjoy :), F3.