A few of my favorites (I think. Should have been documenting these all along, there are a couple I really liked but, typical of me, I can only vaguely recall...):
http://naifgames.com/games/room360/
http://games.gotmail.jp/nigepico/
http://www.newgrounds.com/portal/view/514420
http://www.newgrounds.com/portal/view/486799
BTW, Usually if you find a good/great one there is a series or set created by the same author.
For instance all of these are excellent:
http://neutralxe.net/esc/index.html