I think everyone should sign up for e-mail alerts from their favorite retailers. Reason being, many of my favorites do not advertise in traditional (newspapers, magazines, televisions) manners to keep their costs down. Also, they are able to react quickly to market conditions. For example, Saks Off 5th regularly sent out alerts on deals that lasted for only a few hours throughout the entire Holiday Season. I took several people to the store and watched their jaws fall through the floor at the prices on everything from Prada to Zegna to Gucci.
If you are going to be a shopper, be an informed shopper.