M9 - Shinkansen II by Archiver, on Flickr
2.35:1 aspect ratio.
I am beginning to learn how to compose for anamorphic aspect ratio video, using the Magic Lantern hack for the 5D Mark II and anamorphic framelines. That way I'll have a 16:9 ratio master file and be able to crop to anamorphic in post. I went through a bit of a craze for 2.35:1 images a couple of years ago, but I hardly do it now.