>A Deepness in the Sky, Vernor Vinge mentions the honourable profession of software archaeologist. Any code is written. You only need to find and fix to your needs. ;)

Duly noticed at each reading. Now since we're in fox world here, I've had routines which survived some 30 years with just slight changes. I wish I had the time (read: patience) to create a colored representation to show the age of each line.