I have a dedicated linux box as a firewall/router (with a pretty strict configuration - it blackholes pretty much all incoming traffic). Only certain boxes on my home network can access the internet, and all downloads go onto my server where a virus-scanner is running. All web browsing is done via a proxy. I use Eudora rather than Outlook.
The main remaining vice is that I still use IE6 to surf (though the proxy kills pop-ups and javascript).
I run one of the spy-ware scanners once every couple of days (can't remember which particular one).