Here is a chart comparing the physical sizes of some digital recorders I was interested in. I got the idea from Brad Linder's blog. They are listed in decreasing length measurements. So, although the H2 is bigger than the Yamaha, it is the shortest and ends up at the bottom.
"HEIGHT" actually refers to the thickness of the unit.
I didn't bother to convert all the metric weights to ounces, but it was interesting to see that the Sony with four AA batteries is over 6 times the weight of the Yamaha with one AAA battery.
The Zooms' specs don't include the battery weight.