Close to my work in Luxembourg, there is a supermarket — well, more a French hypermarché. Big does not begin to describe it; it’s gigantic. Humongous. And, in true Dutch fashion, they have a bonus-card-like system. You scan the card, and for some selected products, you get 5% of the price as a debit on the card. On Tuesdays, this is 10% (for most, but not all, products that grant you this). And sometimes there are special offers where you get more money or a larger percentage for a special product.
Over time, with careful planning (shop on Tuesdays! Buy into the hype, buy the products that come with money!), you can accumulate eventually some money.Enough to purchase Zelda: Phantom Hourglass at least :) :) :)
I’ll be trying that out in 3 hrs in the train, most probably :)