"Try and see if your local library wants them."
I don't know where you are, but my local library is going the other direction. They are rapidly thinning the collection because CDs don't get taken out much any more.
Like RichTruss I FLACed them to my NAS and ditched the jewel cases for those lined envelope things. They take up a lot less space than 3000 jewel cases! Having said that, since I kept out the SACDs to play anyway, I have started putting some favorite Redbooks back into jewel cases.
<Insert forehead slap here>
As with record albums I just like the physical aspect of going through the collection to pick something out.