Make a photo book for your kids. I wish my parents would have gotten duplicates of photos from when I was little because now that I am having kids, I want to compare photos of my husband and I when we were little, but our families are very reluctant to part with the photos they love and have had all these years, so start a couple of scrap books to give your kids with photos that you don't mind giving up when they have kids themselves.
Also, duplicate photos and "bad" photos, I put in those cheap photo books that you get for like $0.99 at the drug store and my 2 year old loves looking at the pictures and because they are extras or out of focus or not ones I especially love, I don't care or freak when they get bent as he turns the page, but my son looks and sees his family and feels like a big boy!