I've started the cull with romance and general fiction. Most of the romances are Regencies, and it's a catalog of loss as I look at all the publishers and lines that no longer exist, and the receipts from bookstores that closed long ago. I laughed as I realized that yes, I own four Regencies that bear the title A LONDON SEASON (mine, by the way, was a Zebra Regency 1997 release.)
Moving on to cull the F&SF will be harder, but it's time. Do I keep sentimental favorites like the Star Trek episode novelizations by James Blish? If I haven't read a book in more than 10 years, is it time to let it go? Or do I keep the ones I remember enjoying? My goal is to cut down my book collection by at least half--if there's zero chance that I'm going to reread it, then it needs to go.