Mark Sandman played a two stringed bass with a slide on his pinky. I'm reasonably certain that it was tuned A-D.
A few years ago I was listening to Led Zepplin III a lot and got interested in open tuned slide bass (Jimmy Page plays a lot of open tuned slide guitar on that record). As it happens, I tuned D-A-D-A, similar to what Mark sandman had done earlier. I play a brass slide on my ring finger on acoustic bass guitar.