] The attoparsec/microfortnight is remarkably close to the inch/second. ] Quite useful for quoting tape speeds :-) A friend of mine once made a PostScript ruler scaled in attoparsecs. I just found it and slapped it into my web directory. Here's the URL: http://www.cs.unc.edu/~yakowenk/ruler.ap.ps Of course, this depends on your printer being accurate, but the "B" side is marked off in inches, so you could at least compare with a trusted ruler to see if your printer needs adjustment. Um, PostScript is classic, isn't it? :-) Cheers, Bill.