Ding ding ding ding ding!!!
1) Sometimes spawns in a fixed location on the map - Spawns under a bridge to the Southwest of Middle Park.
2) It is used to activate a side-mission in another game - The Burglary side-mission in San Andreas.
3) Vandalism - Some of them spawn with graffiti on the side.
4) City of Boxes - Box = Box, and Ville = City in French.