Though a few times I have the encounters all predrawn on my giant battle mat and just hid them until the players could discover them. I found that to be really great, and while I like tiles I liked the portability of my mat and not having to place tiles better.
I know I could tack tiles to poster board but that makes them difficult to port, I game at my FLGS a lot.
I do like how the tiles look, so I'm thinking of trying gaming paper and predrawing everything on sections of that.
WotC tiles, paizo flip mats & map packs, wet erase battlemats you name it I've probably used it or am using it right now. I've used minis and a grid/play surface for 20+ years I'm not stopping now!
Custom table and dry erase markers. The DM has a table inlaid with 1" tiles covered with a sheet of glass. Very, very convenient. Just too easy to draw out anything and everything - especially when most people in the group love using/showing off the minis. Incidentally, I also play in an OD&D game and we don't use any mats/grids/squares and no one even has a mini. Interesting to be in both games at once. You really get a feel for the differences.
Paizo flip-mat (best bang for your buck hands down) and minis/assorted counters/pokerchips. Planning on getting some tiles when the Master sets come out. Oh yeah and plastic pop bottle rings, got a ton of those now.