Ravelry has the delightful category for projects known as "hibernating." We all have them. I know I have plenty of them...the projects that somehow lost their allure for me. Typically, they're the ones that have became difficult or annoying to knit. Or the season changed and the project became inappropriate. (Somehow, working on a wool sweater in July in St. Louis just isn't attractive.)
So what becomes of these Unfinished Objects? For me, it depends. If a project has become so unpalatable that I know I'll never get back it, I'll frog it. That decision might be sped up if I want to use the yarn for something else.
But if I think I'm going to actually start knitting a project again, it goes into one of two places. For the ones just taking a nap, they'll languish in their project bags, waiting for me to pick them up again. The ones that are truly hibernating are moved into my Kangaroom purse/yarn organizer, which hangs in the closet. (Note that the picture is from Kangaroom's website, it's not a picture of my own organizer, which is difficult for me to photograph in the depths of the closet). Occasionally, but not very often, I dig around in there and see what's waiting for me. It's cheaper than satisfying my itch for something different by going to the yarn store!
How about you? How do you store your UFOs? At what point do you retire them?