I just played around with the calculator and then accidentally deleted my post.
I tried using drag area (because it is easier to find), speed and distance. I'm not sure what it means but I think I found a fun way to compare a Hummer and an Insight. I call it DRAG VOLUME.
The drag area for a Honda Insight is 5.10 sq ft.
The drag area for a Hummer H2 is 26.5 sq ft.
60mph is 5280 ft/min.
5.10 x 5280 = 26,928 (cubic feet/min?)
26.5 x 5280 = 139,920
The Hummer moves 26,928 (drag volume?) of air in a mere 1016 feet. If the Hummer goes 1016 feet per minute that's just 11.5 mph.