What do I do with all of these slides?

I have a confession to make. I haven't shot slides of my work in over a year. Many of the shows and galleries I am submitting to are taking digital submissions, as I've discussed before here. This lowers the costs of submitting work in all facets. Financial expenses in shooting, developing and copying images are lessened if not made virtually obsolete. The environmental impact decreases (especially when you can submit works via email or through an online system as opposed to mailing in a packet). And the amount of time spent shooting images of one's work, waiting for those images to be developed to see if any need to be reshot, and then reshooting them if necessary (staging everything anew) is drastically lower.

But now I have a dilemma. I have a bunch of old outdated slides of works that are no longer relevant (because they are too old or I don't own them anymore). A lot of these slides are the only images that I own of certain past pieces. But I have a lot of duplicates and copies of slides that I really only need to keep one of for my own records. What shall I do with all of these extras? Are they recyclable (beyond making art out of them)? What do other artists do with old slides? I hate throwing anything away, but I see little need to keep them and am simply not inspired to make art out of them. Please let me know what you are doing with your old slides by responding to this blog post - I'd love to learn of others' solutions to this problem that is faced by all artists nowadays.