Photo by Spencer Platt, Getty Images.
Best Buy e-mailed out a coupon that -- thanks to a lack of restrictions -- caused a shopping frenzy that saved their customers thousands and cost the store a lot more.
The coupon was good for $50 off a $100 purchase if you used a MasterCard. There were a few limitations on certain types of television, but nearly everything else was good with the coupon - including gift cards.
There was also no limit to how many coupons that could be used, with many shoppers reportedly buying loads of $100 Amazon gift cards for half price with the coupon.
Best Buy later released a corrected coupon upon realizing the error.