Adding to the above, of the top of my head:
--power bar for the digital cameras, walkie talkies, cell phones, PDA's, laptop, kiddie night light, gameboys, ipods...
or is that just us?
--room or bathroom deodorant
--can Lysol disinfecting spray (not if you're flying though, I guess)
--portable baby/hand wipes
--stick of stain remover
--ziploc bags ***'ted sizes
--e-mailed Ghirardelli coupons for yummy sundaes at Downtown Disney
--stickers of your own address details to slap on all those electronics/autograph books, etc. (I wrote in our cell phone #)
--batteries, digital memory cards
--that extra bag-tagged empty suitcase/bag for the souvies coming home!
--directions to & address of your resort
--photocopy of back of your admission tix
--ditto on The Crocs!