I saw a good suggestion... can't remember where... that I intend to do; you take a photo of the artwork and when you have a years worth of photos (or any time frame, style, type or grouping you wish) then you make them into one of those photo books. Then you can just pop them all in a bookshelf and look through them again when you want. Sounded really good to me! Might keep a few hard copies of some favourite ones also.