This is a fun thing that I ran across today - someone created a website that compares and shows visually the different sizes of camera sensors.
They are still adding info, but it is interesting to see the size difference between various bodies.
http://cameraimagesensor.com/size/#54,110,74,163,83,53,182,108,24,135,a
It's a Non-commercial site so I thought this would be good to share.
