Have you found a good way to circumvent the system and limit the way your activities and purchases are tracked?

I find “Store Cards” annoying. You know, those cards that you have to carry and swipe in order to get the price that the store has openly posted as the sale price. I don’t like giving them my information, and I detest carrying the cards.

Simple solution? I asked around until I found a friend that already had both Walgreen’s and CVS store cards. I enter her phone number at the register, she gets credit for my purchases, and I keep my anonymity.

Do you have any tricks to get the best price and protect your privacy? In person or on-line?