Maybe there are sites that allow you to open the PDF "in the cloud" so to speak? I'm just guessing here, but the websites Knovel, Scribd, Google Books and more will all let you view "their" PDF documents on-line without actually downloading them. So maybe there's a website out there that will allow you to view any PDF, as long as you provide a link, or upload it to them. Then you can view a PDF of any vintage without installing Acrobat at all (may need a browser plug-in though).
STF