Sports memorabilia, autographed footballs, helmets, hockey sticks, pucks, photos, plaques, bobble heads, baseballs, cards, etc. My place is full of the stuff, much of it is probably worth quite a bit. I have a friend that has remote control cars, boats, planes and such through out his house and my in-laws collect clowns, figures, pictures and such. I guess we're all pack rats to some extent.
I like to have a few mementoes of countries we have lived in or visited, some photos and paintings of the family, things made by grandchildren and then a few objects that hopefully pick out the colour-scheme I have chosen. That sounds like a lot and I really like it to look welcoming and peaceful. Oh, well.