(I also find myself thinking about so much software that has vanished over the years—my DVI previewer for VM/CMS plus the VAX/VMS change files for all the TeX s

(I also find myself thinking about so much software that has vanished over the years—my DVI previewer for VM/CMS plus the VAX/VMS change files for all the TeX software that I maintained in the 80s. There’s got to be a lot of even more interesting software where the only copies have almost certainly long since vanished.)