We don't really collect much of anything, aside from Land Cruisers (stored off-site, fortunately) and wine (and no, that's not a joke - some of it we really do save). I've seen some very cool collections, though. Cooper's parents have friends who collect old binoculars and typewriters. They're lucky to have a big enough house to handle it, and the collection is really great.
A collection is only as good as its display, though. That's what inspired this: