[play on war-driving; the first syllable has
since been reinterpreted as an acronym for wireless access
revolution
] The practice of using chalk marks similar to hobo signs
to indicate the nearby presence of a wireless Internet access point, a boon
to strolling hackers with laptops. The concept was first floated in early
2002 and was instantly seized upon with cries of glee by hackers all over
the portions of the world urbanized enough to have sidewalks and access
points. The process rather recalls the explosive spread of heraldry in the
medieval Europe of the 1120s. There is a site that explains the symbology;.