Sure, if you're hosting close friends or relatives, you'll probably want to prepare dinner during their stay. But when your daughter unexpectedly brings a friend home for the weekend or you're called in to work at the last minute, save yourself time and follow the bed-and-breakfast rule: Serve guests the first meal of the day, and let them take care of the rest. Guests are most likely to be around in the morning, anyway, since they'll be out during the day and may have dinner reservations at night. Provide a casual grab-and-go meal (pastries from a local bakery and fruit are perfectly acceptable, as is tried-and-true cereal), and leave it at that.