I bought several sanding discs for 0.01 cents each at Home Depo in the (rental dept), the girl scanned them and said wow only a penny, she kept scanning them. Regual price was like 4.00 each. About 7 months later I went back, and instead of the tool dept went back to the rental dept and grabbed a handful of discs and to my amazment the scanned for 0.01 cents again.. 7 months later... so I paid and left.
Another time in STAPLES I was waiting in line in a very busy store ready to purchase some software 29.95 when lo and behold it scanned for a penny. THe girl called the manager and he said he doesn't have time, tell the guy this is his lucky day. Cost me a penny.
It happens...