Food
If you want to eat something in Prague (you propably want), cheapest is just go to some supermarket.
But beware: there are fraudulent minimarkets.
If you walk into a shop and there are no prices on the products, walk away.
But even if the prices are written, especially in the centre, they can be very expensive (sometimes more than 5x).
The best places to shop are the larger supermarkets:
