I really like anything to do with astronomy from the past. I recently acquired a set of astronomical slides, which are fabulous even if they are more than a little historically inaccurate. They seem to have been produced in the mid-1970’s as there is a slide of the Pioneer 10 space probe which was launched in 1972, with some of the slides being dated 1976/7.
My favourite slides include an asteroid colliding with a black hole, or maybe the terraformed Moon. Also shown below is a comet on collision course with the Earth- scary stuff, but then the slides were made in the 70’s 😱