We found music really helped - had an ipod hooked up to a good speaker system and kept creeping the volume up as the labour progressed...there were people wandering the halls of the labour ward wondering where the party was!

Lighting makes a big difference to the environment too - some rooms seem to be pretty good in the regard, but you can always bring in your own light to soften the room up a little.

Slippers - if you're going to be padding around a hospital floor in the room, or bathroom then something to have on your feet is better than cold tiles.

Cups or Mugs - cuts down the number of trips to the ice machine, and it's much nicer to hold than the disposable things that the hospital supplies.