The entire sky, including the Sun, is a projection by the Conspiracy onto an enormous canvas sheet 3000 miles high.
Okay, so the sun doesn't actually exist. A number of problems with this.
1) Where does all energy on Earth actually come from then?
2) Fossil evidence of plantlife existing well before projectors were invented sort of screw up that theory. (Yes, plants DO need light to survive. I once put a plant in a dark cupboard. It died, and went a funny colour. Because there was no light. Obviously.)
Also
3)
http://en.wikipedia.org/wiki/List_of_oldest_trees Pretty sure most of those were already rather large before projectors were invented. How did they grow without light? Peculiar, don't you think? Oh wait, no, it's obvious... "The Conspiracy" has actually secretly invented time travel unbeknownst to us mere mortals. They've gone back in time and created life and held a projector to the sky for 4 billion years to make sure it grows big and strong.
4) You know, all light from the sun is unpolarised. But as soon as it reflects off of anything, it becomes polarised. This is how 3d cinema works. If the entire sky was a projection, then whenever we put on 3d glasses, we wouldn't be able to see the sun unless our heads were tilted at the right angle. Hey, you know what that means! They could show 3d films on the friggin sky! Man that'd be awesome. They could make loads from advertising, don't you think? I need to get in touch with these conspiritor guys, I gotta sell them my idea!
5) This would also mean that anything flying infront of the "projector" (assuming it's on Earth) would put a shadow on the sky. Such as a bird. Or an insect, or, you know... dust, debris, or... you know... clouds....(unless clouds are also part of the projection? THEN WHO WAS RAIN?) I Dunno about you, but I haven't seen many shadows on the sky. That would be a dead giveaway! I reckon if I was a "conspirator" I'd just take the piss with the whole world and put a "Batman" sticker over the projector... would be fricken hilarious. I'd probably get sacked though... although these guys are pretty ruthless, they'd probably just take me out to the "Ice Wall" and shoot me.