Do you remember the name of the manufacturer or company
that sold them?
I'm sure the kit I bought was from Kensington.
I know they sell (or sold) these kits, and have (had) ones for the
Powerbooks. For those it was a little cynlinder with a finger on the end.
You slipped the finger into the security hole, then when you turned the
key, it spun the finger behind the plastic of the case, latching the
cylinder to the powerbook. Then the cable would be fed thru the cylinder
(or was maybe preattached, I don't recall), and the cable was secured to
some other item to keep it from being moved (desk, cinderblock, really
really big dog...)
I also recall a different laptop security product. It was a stick on
alarm that was motion sensitive. It had a keypad on the top to type in
your code to deactivate it. The idea was it glued to the powerbook, so
you could put the powerbook down on a desk, turn the alarm on, and walk
away. If anyone moved or touched the powerbook, the alarm would go off.
I'm not sure how much use it was. If you could run fast, you could still
steal it since it wasn't fixed to any object. You would just run with it
beeping (stuff it in a bag full of rags and it would probably silence
enough to be able to hide it until the battery died, or you could pry it
off the powerbook).
I'm pretty sure these only came in a glue on design, and I'm not sure
when I first saw one, they might have been after the Portable was
retired. So if you need something that is specific to the Portable's
security hole, then that didn't help you (but it was a fun read anyway).
-chris
<http://www.mythtech.net>