I was catching up on some blogs at Planet SUSE and came across OpenSUSE Linux Rants, a blog I followed for several years when I was using openSUSE instead of Ubuntu.
Scott wrote about iptables and how to block hostile machines at the kernel level. He then mentioned a cool little tool called Online IP Subnet Calulator. It would have been nice to have when I was studying for my MCSE back in 1999.
Drahusz 