After Googling some more I discovered that, in Knoppix, all inbound ports are turned off by default. Cool.
Thanks all.
I just did something incredibly stupid. I have an old Knoppix 5 distro on CD back from 2006 that I booted up from.
I accidentally left it booted (on a notebook with Windows 7 Ultra on its HD) all night with the internet cable plugged in.
I searched Google this morning to see if a default firewall is included on Knoppix and discovered that it isn't. So my machine was laid bare all night with only Port 80 and Port 25 blocked at the IP. What are the chances my machine was rummaged through overnight?
After Googling some more I discovered that, in Knoppix, all inbound ports are turned off by default. Cool.
Thanks all.

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