Hi.
        In my opinion, they are useful things. Inside there is no more
than a chip doing the conversion from a parallel port to an IDE port.
In www.shuttletech.com you can find the chip used. With them you can
have an external CD (5.25" units), useful for portables.
        They may or not contain a power supply from AC. If not, probably
they are supplied from the +5V in the kb connector; if this is not available
(some old portables) you would have to open the portable and get +5V (and
pray so that the power supply delivers enough power).

>
> Some recent ads for a portable/parallel port enclosure which holds an
> ordinary IDE hard drive, and plugs into the printer port..  Claim is
> that it works like a 'parallel' port Zip or Syquest, with any hard
> drive up to 4.3 gb.  Anyone try one of these?  Price is right at $80
> if it works.
>
************************************
Javier Vizcaino. Ability Electronics. [log in to unmask]
  Starting point:        (-1)^(-1) = -1
  Applying logarithms: (-1)*ln(-1) = ln(-1)
  Since ln(-1) <> 0, dividing:  -1 = 1     (ln(-1) is complex, but exists)