In large computer rooms, sometimes called data centers (hey, it's a neat term), raised floors are commonplace. They generally serve two purposes; they allow you to run your cabling underneath the removeable floor tiles, which is extremely convenient when installing new equipment, and they also provide a plenum through which air conditioning can be piped. This allows equipment sitting on the floor to be cooled from the bottom up, which is much easier than running ducts down from the ceiling.

I always thought raised floors were cool; rooms with them have this legacy feel to them. It's difficult to describe. Another primary advantage to raised floors is that you can't walk on them without making noise; this makes it difficult for bosses who like to sneak up on you, stand behind you for five minutes, then ask you how your day is going.

Raised floors are frequently accompanied by impressive power distribution grids and a few Lieberts.