The police auction has always been a depressed and homely cousin of the chipper yard sale, a gray Saturday morning in a municipal back lot, grim strangers sifting through boxes full of other people's losses. Do I hear $2 for the boy's mountain bike? Very good, sir. What about $3? Those days are over in New York City, whose Police Department has joined some 300 others around the country in clearing out crowded property rooms online, unloading hundreds of television sets and car stereo speakers, leather coats and compact discs, cellphones and anything else that once belonged to someone else...