On vacation and staying with nephew. my wife and i were driving east on kismet pkwy west, cape coral, fl. we were observing and noticing how much the area was growing. looking ne i observed a dark grey rectangular object ascending up from behind the distant horizon. at first i thought it was a para-glider with a very large wing. however a para-glider cant ascend straight up. i pointed to where the object was and my wife also thought a para-glider. however there was nothing hanging below the gray rectangular object. i then decided to get what video i could on my cell phone. because of traffic and trying to stop i was only able to get 35 seconds of video. as the object headed in a westerly direction its speed started to increase. i turned around and proceeded west bound at 45 mph speed limit but the object quickly exceeded double my speed in a nw direction under the clouds and while negotiating traffic we looked in direction of object and it was gone. nothing emitted from object. did not observe any windows, lights, landing gear, wing(s) , or vertical stabilizers. no other aircraft in vicinity before or after event. (i'm a pilot with over 800 hours flying civilian, 200 hours flying military observer) i have 35 seconds of digital video on my cell phone but dont know how to attach it to this report