Well... my old Tosiba 420 did/does that once in a while, and it's six
years old. My IBM Thinkpad is over a year old - every once in a while it
goes 'ka-clunk' as if some solenoid (which of course there isn't) in the
HD activated. It's disconcerting, but so far innocuous.
That being said - I have a cute little PCMCIA - to - HD adapter and
software (Simpletech DriveLink) that does a mirror-image copy from the
internal HD to another one attached to the adapter. Then you can use the
new one for backup, or replace the existing one. It took about 1.5 hours
to transfer 6 actual gigs of Stuff from one 20G drive to another.
It cost $89 plus whatever drive you buy. Its one of those things like
drive de-fragmenting - set it working one evening before you go to bed and
in the morning you'll have a new back-up drive.
The other thing DriveLink is good for is if you have to get a large
amount of data physically transferred from one machine to another - the
external drive just shows up (in Windoze, anyway) as one of the mounted
devices, so you can move Humongous Files back and forth as needed.
Hope this helps...
Cheers
John