Old PC as hardware firewall.

Hi all.
I have a very old PC knocking about and i've just read an article in my favourite weekly PC mag (Micro mart)about "Great uses for an old PC".
One of the options was to turn it into a firewall.
From the mag..
All well and good but how do i do this?
The specs for the (very) old PC is_
Celeron 500MHz processor
64mb PC100 RAM
8gb HDD
Windows 98se.
Would it work? What do i need? Crossover cable, router....
I'm currently on 4meg cable broadband.. the modem is supplied by the ISP.
Any thoughts would be welcome!
Cheers,
Rob.
I have a very old PC knocking about and i've just read an article in my favourite weekly PC mag (Micro mart)about "Great uses for an old PC".
One of the options was to turn it into a firewall.
From the mag..
it provides a physically separate and secure barrier between the internet and your PC..
All well and good but how do i do this?
The specs for the (very) old PC is_
Celeron 500MHz processor
64mb PC100 RAM
8gb HDD
Windows 98se.
Would it work? What do i need? Crossover cable, router....

I'm currently on 4meg cable broadband.. the modem is supplied by the ISP.
Any thoughts would be welcome!
Cheers,
Rob.