What's the best way to wiretap a network?

You can plug a mini-hub in line and use that as a tap point to monitor

> the stream. Up side is its cheap and easy. Down side is you have to
> drop to half duplex. Not a problem in most situations but in some the
> drop in performance can be an issue.

Don't throw out your old hubs. It's hard to find a 10/100 hub for sale any more. Even the cheap consumer devices are switches. I picked up a $25 hub at Fry's a few weeks ago just in case I ever wanted to casually snoop some traffic. But Fry's is sold out.

The netoptics.com link posted was "priceless". I'm always wary of
simple products that are expensive enough to have a request for quote,
rather than a price, on their web page.