RadioShack.com is having a cash off sale now through October 31, 2011. A $90 minimum purchase is required, limiting the savings to high ticket items like smartphones.
No codes or coupons are required but to get the discount you must click one of the special image links below. The discount will appear in your shopping cart as soon as you add qualifying items totaling the minimum amount. Be sure to use the proper link for the amount of your intended purchase. If you use the $5 link, five bucks is all you will save no matter how much you spend.
As is always the case with offers of this sort, "restrictions apply". The Shack isn't telling us what these restrictions are but I tested the links and they do work on prepaid phone purchases.
Save $5 On Orders Of $90 or More
Save $15 On Orders Over $125
Save $20 On Orders Over $175