A nice article although it doesn't mention some of the specialist distros like SME server, Nitix, ClarkConnect and the other gateways which are suitable for setting up a machine for use as a firewall or NAS unit. SME server in particular is fantastic - get it at www.contribs.org it's good out of the box but when you mod it you get a fantastic server for nothing, that's a price that is hard to beat.

For security people the live cd Whoppix distro is also pretty amazing you can be hacking oops...... penetration testing in the time it takes to boot from CD.