Always remeber maternity pads and breast pads. And of course newborn nappies and maybe some nipple cream as they can hurt in the first few weeks
CAR SEAT they wont let u take lo without one, black granny panties, comfy clothes as ull still look about 6months preggo, extra super absorbant maxi pads (the ones at my hospital were like a queen mattress), belly wrap if ur using one (ur guts might feel like theyre falling around when ur up walking around) lanolin cream if ur bfing. Just expanding on sprmom87s list a bit
Outfit to bring baby home
Comfy clothes for you
Toiletries
Extra undies
Sports/nursing bra
Flip flops
Chargers
Camera
Things to keep you occupied
Change for vending machine