Hi,
I had to dig out some ancient drawings (HPGL, gerber set) late last night. Of course, the originals from which they were created are not readable by anything "modern" (but, then again, this is probably true for many things from 2009!).
Thankfully, I have kept all tools and suitable hardware to run those tools on so that I can recover these sorts of things.
But, it begs the question: what is the tool-du-jour for reading/viewing/printing/converting *common* >>>OUTPUT