Adventure Thru Inner Space was always my favorite ride at Disneyland. It was so moody and unusual that it took you out of reality into a great constructed environment. Unlike the other rides that tried to replicate other time periods or locations, Inner Space took you to the microscopic world. Since that world is not observable visually, it has to represented in a new abstract language. And the Paul Frees soundtrack and crazy music just added to that wonderful experience.
Since it was such a strange attraction, Disneyland did not make many souvenirs other than a little booklet and a record. I have the giant attraction poster but have never gotten it framed. So in the end most of what is left of the ride is our memories and remembrances.