Thanks for the info. I was only using the IP address as a "what if". For example, I could imagine a situation where I might have the following:
$string = "My IP address is 10.1.1.1!\n"

Or, better yet, what if I had a function that grabbed my current IP address (let's call it $IP) and then I changed the above to:
$string = "My current IP address is $IP\n"

Thanks in advance, I'm just trying to grasp this more fully. It is certainly a neat item to mess around with...

Also, is this discussed in any of the O'Reilly Perl books? Mine are at work right now, but I'll page through them when I go in tonight.