The 1930 REO Speedwagon "Milk Bottle" truck is a famous vintage commercial vehicle with a custom aluminum body shaped like a giant glass milk bottle.  The truck used a standard 1930 commercial chassis built by the REO Motor Car Company in Lansing, Michigan. Ransom E. Olds, who also founded Oldsmobile, started the company in 1905. The famous rock band REO Speedwagon later took their name from the company's famous delivery truck.  Only three of these unique, bottle-shaped advertising trucks were originally manufactured. Historical records link them to regional dairies like the Berwick Creamery in Pennsylvania and The Luick Dairy in Milwaukee, Wisconsin.
More pics and information here.