This might be the easiest idea ever and I am sure there are many variations of it that would make it even cuter. I made this ornament a few years ago when we were celebrating our first first Christmas in our rental home together. It is the key to the place I lived when we started dating where we spent tons of time the first 2.5 years of our relationship. I am about to make another one for our rental home and maybe one from our new home as well.
This was as simple as taking an ornament hook, putting the key on it, typing the address on a piece of cardstock, putting it on the hook and tying a ribbon around it. I'm thinking of glittering the key to make it a little prettier but this is how it has been for the last 2 years.