Little bumpers

You've seen these little stick-on bumpers, haven't you?  If not these, then surely something similar.  They are like duct tape - they have 100's of uses, especially on a boat.

stop doors from rattling

I promise you that if you buy a pack, you'll use them all up.  So buy two packs.

Here are some ways I've used them:

to protect woodwork (the bumper's down there in the lower right)

as a cushion between the head lid and the wall