Here it is, my 1000 card EDH deck (999 cards plus the general).
I play with the deck in a long box. 1000 cards in penny sleeves don't quite fit in a normal long box, so I had to construct a special "longer box" which is a few inches longer. :/
I try to avoid tutors in the design (for obvious reasons). When I do tutor, I look at only the first 50-ish cards, take my pick, shuffle the rest, and put them in the far end of the box (bottom of the library).
I put in some extra draw effects and mana ramp, so the deck is more reliable. When you have a 1000 card deck, there is a threat of a huge clump of some kind. I've played this deck many times, and thankfully it's behaved very well.
This deck has pretty much every dual land / multi-land in existence; even the really bad ones.
Click here for a text version of this decklist
Click here for my EDH Commander decks