This isn't ground breaking art by any means, but it certainly makes my list as unique - simply because of its presentation - art on a penny. Also, the work is quite well executed - in fact, I love the whole concept. May favorite may be the work/cent second from the top in the example below. It's titled "Kisses and Ghosts, 1951".
More can be found about the work and the artist - Jacqueline Lou Skaggs - at the following link.