When I checked out of the Key Bridge Marriott, I left a brief hand-written note directed to the GM thanking them for a several moments of good service over a long trip when I needed a lot of accommodations -- nothing major, just many little things like storing food for me in their refrigerator, bringing me extra bath robes, etc. A couple of weeks later I got a note from the GM mailed to my home thanking me for my patronage and for the compliment. Nice.