This is an Antonov AN-124 "Ruslan" cargo plane at DTW. I filmed it this morning from my cab with my Coby Kyros tablet.  It's one of the largest aircraft in the world.  This image is crappy and I didn't have time/access/equipment to get a better shot but I observed the word "Antonov" on the vertical stabilizer and the words "International Cargo Transporter" on the nose of the plane so I think it's an Antonov Airlines plane.
This for me is right up with the Ford Trimotor I saw at the Ann Arbor Airport, a Concorde I saw on at JFK, a B-1 I saw while climbing in the Tetons, and the time I looked up in the air and saw a mid-air refueling in progress. Oh, and maybe the Super Widgeon. Just think, my brother used to work at an AFB that AR-71s flew from!! Here is an official photo of the AN-124: