>>601987
I know that this is probably bait, I'll bite. Buy a weather balloon. A $20 one should be good enough, and you'd need $40 for the helium if you can't get it cheap. Attach a video camera pointing to the horizon. You probably already have one of those. Also attach a tracking device and a parachute so that you can get it later.
Congratulations, if the camera didn't point the wrong direction, you've got photos of a curved earth.