I love it too. What a shame people throw books in the trash in the first place.
That's sort of what brought me to BookCrossing to begin with. I bought a copy of The Da Vinci Code, to see what all the hype was bout. (This is back in the day, when there WAS a lot of hype about The Da Vinci Code). I finished it alright, but I thought it stank and didn't want it cluttering up the bookshelves...but, no matter how bad the book is, I wouldn't feel right about throwing it into the bin.
By coincidence, a few weeks after I'd finished it, I saw BookCrossing mentioned in the newspaper. I was delighted - a guilt-free way of getting Dan Brown out of the house !