The last year or so, I've been hand-painting posters for my day job at the LIU Brooklyn Campus Library Media Center, having fun with some different genres. Here's the three I've done so far.
They're all acrylics and cheap poster paints and watercolor on heavy duty contractor's paper. I found a roll of paper in a dumpster and thought I'd put it to use. I started with the robot one, which was inspired by an old serial, then the musical one, which was inspired by Busby Berkeley musicals, and the beach one is up now. That seemed right for summer. For the fall, I might do something inspired by Pam Grier action movies from the 70's, though I'm not sure about that yet.
And I guess they're all inspired by the posters you see made all around the world, just that kind of handmade, casual, folky appearance. And they're all the size of a big bulleten board, about four feet tall by six wide. Approximately.