Just my luck!  I'm making the final backup copy of
my old Mac G3,
 and one of the drives dies, and my other backup wasn't.
 I take it apart - it's a 20 gig IBM Deskstar DTLA-305020, just
 old enough for the (cough) ten-year-rule, and well-known prone to
 two modes of failure, click of death and NVRAM failure.  I'm hearing
 the NVRAM failure sound as shown at:
 
http://www.dataclinic.co.uk/ibm-deskstar-hard-disk-drive-data-loss.htm
 In googling, I saw one reference to someone replacing the 8-pin NVRAM
 themselves from a donor drive, but that seems risky to me.
 I think I'll send it to 
Gillware.com, a Madison, WI-based recovery
 place.  They offer $400-700 Windows recovery but charge a premium
 for Mac recovery ($700-$1000) and Linux ($800-1000), with the higher
 price for "clean room recovery".  (Hmm, I thought bits were bits.)
 Any other advice - besides a better backup strategy?
    
I found this place to be very reliable, no fuss, no hype, very
professional, and it doesn't matter what OS was being used.
And they have a comprehensive list of info on the many drives and their
common problems, don't get disappointed in their review of the concerns
they have for the quality of your drive. It's a good reality check when
you read about all the defects that occur--even with the modern drives
they make today. I had a brand new WD 500GB crash after only 11 mon. So
now I use dual 1TB drives to backup everything.