I no longer had a 35 mm projector that worked, nor did I want to get another at the Goodwill store. And I did want to get rid of my slide trays.
ScanCafe sounded like a reasonable alternative - put them on discs. To be sure, I sent in a small order (about 150) - they came back great. I grabbed the rest (about 500) put them into plastic bags and sent them all to ScanCafe. (The trays I generously donated to Goodwill [what do they do with them?])
Loved the result. Sorted them into catagories and deleted some when I got them all back. I am now consolidated and can see them on the big TV screen when I want.