After some experience; I find that the best items I have brought from home that are very easy to pack and just come in too large amounts or too expensive to buy there are:
Coffee filters, sweetner packets, straws, box of ziploc bags, sometimes my own coffee, dryer sheets, laundry detergent that easy to pack, tea bags, wet wipes,small salt n pepper and always my handy can of lysol for disinfecting the remotes/lightswitches, bathrooms and door handles (My whole family was sick with a terrible flu once in a hotel for days passing it around and I would hate to be the person who came in after us, it was highly contagious and i don't think most cleaning companies do a thorough job, so now i spray everything myself, who wants to be sick on vacation!)