I'm not the best to answer this as I'm only 10 wks and on my first baby lol, but I have read some stuff that I thought was a good idea.
Snacks for you after baby is born and for your partner. Who knows how long it will take for the kitchen to send up some food.
Entertainment - book, ipod, whatever for the down time...apparently there could be lots of waiting.
Bathrobe and slippers
Sanitary pads, breast pads - I guess if you bring your own the hospital shouldn't charge you?
Make up - even though it sounds vain, "the book" says you will be taking lots of pictures and you will want to look good. I know I'll be taking this just because of my MIL comment about DH's cousin after she gave birth: "Look at her in this picture, she looks like death warmed over." How rude!
Anyway, hope this helps even though it's all from my book