I have a Tesco Loyalty Card, it gives me 1% on all my shopping apart from some special offers which may give you 2%. Every quarter I get a statement from them and cash vouchers which can be redeemed in store for their face value. You can also trade them against all sorts of things from affiliated companies, and sometimes your points can be worth quite a lot more in those circumstances. I know I pay for it in the end, but it's nice to get the price of a decent bottle of Malt Whisky back through the post 4 times a year.
Giok