Old route maps: they're on your computer!
...if you have the electronic timetable, that is.
I just downloaded the most recent update of the electronic timetable, and in my c:\program files\United Airlines Eletronic Timetable directory there are now a few really interesting old BMP files. Check out iasia.bmp, naeast.bmp, nawest.bmp, and inamer.bmp.
It's the old-style route map, with lines drawn between all the cities served. I figure the maps are from around December '99 based on the file dates, and routes shown include JFK-CCS, MIA-LIM, KIX-MNL, LAX-KIX, and HKG-BKK--but no SIN-HKG.