TV's longest-running game show "The Price is Right" premiered on this date in 1956. Today also marks the biggest shopping day of the year. Here's what you should know if you are going out to buy nails. There are two types: common nails and finishing nails. Common nails have large flat heads and are for rough work. Finishing nails are thin and can be driven below the surface with a "nail set." Nails are sized by the "penny system" -- a number, and a small letter "d." You can gauge how long a nail is by dividing size by 4 and adding a half-inch. An 8-penny nail would be 2 (8 divided by 4) (plus one half inch) -- 2-and-one-half inches long. To get the best price, buy in bulk instead of those little expensive packages. And that's the On The House tip for today.