The brick island, topped with maple, works equally well for informal dinners, food prep, and cleanup. (bostonmagazine.com)
A fireplace lined with stone tiles will give you all the needed warmth for both formal and informal dinner parties. (designtrends.com)
Simple brown kraft paper looks great too, or you could use a roll of black paper to mimic a chalkboard; I've done this for informal dinners with friends and it looks gorgeous when decorated with white chalk pens (leave some on the table for guests to doodle with..) (katescreativespace.com)