The “How Posters Work” show at New York’s Cooper Hewitt Museum is not to be missed:

http://www.cooperhewitt.org/events/current-exhibitions/how-posters-work/

View their slideshow here:

http://cooperhewitt.photoshelter.com/embed?type=slideshow&G_ID=G0000WHi3x_2pNVY#!/slideshow/I0000DjTetN.c_ag/null