Who would have thought that a 20-cent price cut could make such a difference? In the month since the (legal) digital music service Listen.com cut the price of its downloads from 99 cents to 79 cents, it has nearly doubled the number of songs it sold. The price cut was initially a response to the much-ballyhooed new download service offered by Apple, but Listen.com (which is owned by RealNetworks) wound up with 11 million songs downloaded from its servers in the month of June.