Dot-matrix bicycle printer

(from http://www.boingboing.net)

jkinberg has invented a bicycle that doubles as a dot-matrix printer,
huffing out low-resolution ASCII characters from an array of spraychalk
cans mounted on the bike's rear and controlled by a Powerbook. He's
planning to make a bunch of them to spray anti-GOP messages during the
Republican convention -- he calls the project "Bikes Against Bush."

http://www.bikesagainstbush.com/

Not much detail at the site though

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