I have a t-shirt with a map of Nantucket that I bought when I lived there 12 years ago that was too small to begin with and then shrank in the wash. But every time I decide to prune my t-shirt drawer, I look at it, sigh wistfully, and put it back. I cannot bring myself to throw or give it away. What am I going to do, cart the thing around with me for the rest of my life? And then what, leave it to someone in my will?
I also have my old address book from when I moved to America. I brought it with me to keep in contact with people back home. Not everyone had email back then, and those that did wrote their email addresses next to their names before I left. I don't think there's one single detail in that book that's still correct today. Yet I can't get rid of it. Just looking at my handwriting from years ago makes me feel all sentimental.
But on the other hand, I know that throwing away crap like this can be a cathartic experience and leaves you feeling lighter and less cluttered. A feng shui practitioner once told me a neat system: take all of those things which you don't use but can't bear to throw out and put them all in a large trash bag in the closet/garage. If, after one year has passed, you have not opened that bag, throw it out. I'll do it some day.