The Billboard Art Project

The Billboard Art Project is a publicly funded non-profit organization that repurposes billboards usually used for advertising into a public art venue.  Here is a photo I found on Google+ giving you a visual example.

Past billboards have been located in Albany, NY, Detroit, MI, Salem, OR, Richmond, VA, San Bernadino, CA, New Orleans, LA, and more!  Upcoming billboards will be in Quincy, IL and Atlanta, GA (which will be used as a venue for almost an entire month).

Here is an interview with an artist that had work in Duluth, MN: