I don't mean for this to be a serious comparison, but the difference in size is jaw dropping. It gave me a kick, and I thought others might be entertained by it.
The image is from
Compare camera dimensions side by side.
Regarding the
Compare camera dimensions side by side site, I don't think that dimension and weight comparisons tell the whole story. For one example, I have an Oly E-620 with a 25mm pancake lens. That kit weighs 595 grams, and yet it is much less comfortable to carry one handed than the K100D with the FA 35mm f/2 lens that I owned several years ago. The K100D and lens weighed 264 grams more, at 859 grams, but had a better grip. (The K-5 with the 35mm f/2.4 actually weighs close to the same amount: 865 grams.)
Jeff