Messenger Bags

First a little history:

The messenger bag as we know it today, however, originated in the 1950s or thereabouts, being produced as a bag for telephone linemen, by Globe Canvas/De Martini in New York. The linemen needed a bag they could easily access while climbing telephone poles, and this design worked perfectly. New York bicycle messenger companies picked them up sometime in the 1970s, and initially were purchased one color per company, as identifiers of a sort. For a long while, NYC was the bastion of the messenger bag - until things started to spread in the 1980s.

A list of bag manufacturers can be found here.