Collectors will be able to buy another piece of music history on August 15 when auction house Bonhams hosts the sale of items from Abbey Road Studios in London.  Included in the lot will be an upright Challen Company piano from Abbey Road's famous Studio Three.  The battered old instrument is marked with coffee stains and cigarette burns, yet is still expected to bring as much as $250,000 because of its history.  The piano was featured on Pink Floyd's album "Dark Side of the Moon", and was used on the Beatles' tracks "Tomorrow Never Knows" and "Paperback Writer".