Network Card alias

[Tomt <tomt@the-pentagon.com>]

I've been messing around and got IP Masquerading working on my ppp
connection.  Now I want to get it working on a network connection to the
inet like a T1 or other dedicated line. 
I've heard that there is two ways I can go about this 1. 2 network cards in
my Hamm box or 2. Create an alias to my existing network card

Is this true? 

And yes I have heard that choice number two is not a good idea.

If I was to want to go about using choice 2 what do I need to do to create
an alias to my existing network card?

Thanks in advance

Tomt