I work at a university and I used to work in the football stadium (yes we have random regular offices there for some reason) and on game weekends they would pop popcorn by the quadruple giant red see through trash bag full. The smell upon entering the stadium on those Fridays always reminded me of the smell upon entering MK. Sadly my office is no longer at the stadium and I really do miss the smell envoked memories!
My other favorite smells are Rome burning, Poly lobby, POTC, pie in Philharmagic, and my new favorite YC lobby.