I have a Maxtor OneTouch 200GB external hard drive that I brought home
from school with me for Spring Break.  Naturally though, I brought the
wrong power supply unit.  I have an iGo Juice 70 power
adapter/converter that has interchangeable tips allowing the user to
provide power to a variety of different devices.  However, I'm not
sure if the tip that seems to fit my Maxtor hard drive (tip number 4 -
the same tip used to power an IBM 600x) will deliver the proper amount
of power so as to NOT fry my device!  I would really appreciate it if
you could assure me that tip 4 will work, or recommend an iGo tip that
DOES work, I would sincerely appreciate it!

Your Maxtor OneTouch 200GB external hard drive requires a 12vdc - 3a
adapter for power.  Your iGo Juice 70 power adapter/converter has an
output of 11.75 to 16vdc and up to 70 watts.  (These specs are from a
google search of the products).  At 12vdc, the iGo Juice can produce
up to 5a.  So the iGo Juice adapter should work for you if the
connector fits and assuming the polarity is correct (which it should
be as most are standard Plus internal, Minus external). It would be
nice to have a VOM just to check it out.

Good Luck
Jack