I collect ephemera. Paper things. I have boxes and boxes of paper. Some of it is sentimental, some admired, some found. I have pages torn from magazines, bookmarks, greeting cards of all varieties, photographs, prayer cards, artwork from my kids. Some of these mine, some found tucked inside of used books. I sold books on the internet for about 8 years and I compulsively collected the things I found inside of them. All of the above items, as well as grocery lists, utility bills, letters (even a few love letters), recipes cut from newspapers and magazines, obituaries, wedding announcements, place cards, business cards, award ribbons, you name it...basically if it's flat and useful for marking a place, people will stick it inside a book and forget about it, lol. So I've collected these things and I'm quite fond of them. I know it's weird.
I've also been known to be a collector of newspapers and magazines, but except for my Economists and a few Adbusters and National Socialist Reviews, I've gotten rid of most of those. Oh, wait, I still have a good size stack of NY Times Magazines, too. But in my defense, I haven't read all of those, yet.
I've also accumulated quite a few books in my day, but I'm currently in the process of thinning those out.
I do have the realization that if I allow this compulsion of mine to run willy-nilly over my life, then I could easily become one of those weird little old ladies you see on the 5:00 news being carted off to the retirement asylum because her stacks of newspapers and shit have totally overtaken her entire house, lol. So I try to keep it in check.