A surviving internet data packet that once travelled strapped to a pigeon's leg is closing at Christie's today, 13 October, after attracting a bid of $4,000 — already above its $2,000–3,000 estimate. The lot is offered in the house's online-only Fine Printed Books & Manuscripts Including Americana and Science sale, which Christie's frames as an example of the internet's tradition of the artful hack. The story begins on April 1, 1990, when American network engineer David Waitzman published RFC 1149, a formally written internet standards document titled A Standard for the Transmission of IP Datagrams on Avian Carriers. Written as an April Fools' proposal, it described how carrier pigeons could transport IP datagrams, noting that avian carriers offered high bandwidth even if latency was another matter. Most readers treated it as a joke, but the Bergen Linux User Group decided to build the thing. On 28 April 2001, the group tested RFC 1149 using racing pigeons, printers and scanners: IP packets were printed as hexadecimal strings on strips of paper, attached to the birds' legs and flown between two lofts about five kilometres apart. Nine packets went out and four replies came back, a packet-loss rate of roughly 56 percent — a working network in the loosest sense, with no router or fibre involved. The lot is one of those transmitted packets: a small scroll of paper measuring 41 by 210 millimetres, still creased from being rolled up and tied to a pigeon's leg, now framed, with an inscription on the reverse identifying it as the property of Waitzman, to whom it was presented in 2002. A quarter-century after taking flight, the paper packet has become an unlikely collectible — possibly the most expensive ping ever sold.