I have a few books that are too loved for PBS, but hate to just toss. Still very readable.

The Stars My Destination -Alfred Bester

Citizen of the Galaxy - Robert Heinlein

Under Pressure - Frank Hebert

Inherit the Stars - James P. Hogan

Long After Midnight - Ray Bradbury

Public library? Used bookstores might not want them either.

You could consider releasing them in a public place to be found by someone new.  It's called bookcrossing.

-Tom Hl.

Or if there is a food pantry in the area, they often have a spot for books.  I give mine to neighbor, most still postable, but not wish listed, or with some very minor defect, and she takes then when she works at the pantry.  Says they disappear fast.  Mine are mostly mystery, paranormal, UF, techno-thrillers, stuff like that.  You can also offer them free to a church or charity rummage sale and let them give them away.

I won't give away books with real water damage, mold or other serious problems.

There's also a damaged book thread in the Book Bazaar discussion thread.  If you're willing to mail them out without getting credits in return, there's almost always people who will want them.

And if you have more than a couple, you could join us in the upostable book box.  We're always happy to have more join in.