Possibly not a "drone", but interesting nonetheless.
From MUFON:
Date Submitted: 2010-05-18
Date of Event: 2010-05-17
Short Description: The "plane" had no windows
Location of Event: CO, US
Long Description:
I was driving south on Broadway heading to work (between Arapahoe and Mineral) I work 3rd shift. I first noticed it coming over the tree line from the SW heading NE towards DIA. But it could not have been more than 500' up To low for DIA,and heading the wrong way for Centenial. As it was aproaching I turned down my radio and roled the window down all the way. heard nothing (there was trafic noise though). As it was passing over Broadway in front of me I realized there were no windows on it. The wings on it were not shaped like conventional ones they seemed to come out to a point and the tail section looked way to small for the "plane". The fuselage was long and thin. I also noticed no exauhst.The feeling I had was I have seen this before then it hit me,the Utah aircraft mystery. Not exactly like it but very similar. My best gues was it was a 100 to 150 feet long I lost sight over the tree line to my left snd behind me. Upon reflection it could have been coming from the Air Force Acadamy. A drone?