I was up at 4 AM central time (3 AM mountain, which Denver is on) and got running. I fueled up in Limon, Colorado then blew into Denver a few minutes before the 7 AM deadline for dropping loads at this particular place. They let me drop the trailer in a back lot and sent me out a few blocks away to a drop yard to pick up an empty.
There is, of course, no empty here at this time. So I'll be waiting for a while.
UPDATE: It turns out my MPG for yesterday was around 4.4. Yetch.