Hyperion;
I've got 3 machines on my network at home, so here's some tips...
1. A DSL or Cable connection is required.
2. A wired network is cheaper and more secure.
3. The most expensive components of your network will be the cables.
4. Use the firewall software supplied with your router. (Could cause security problems if you don't)
5. Stay as up-to-date as possible on your Anti-Virus Software.
Yes, these are all first-hand experienced lessons that I had to learn the hard way.
