Tiny Core Linuxis still going strong (http://www.tinycorelinux.net/). They're now up to three images, all built on the idea of running out of RAM with a 3.0-era kernel. The Core image is CLI-only and weighs in 8 MB; TinyCore adds a GUI/WM interface at 12 MB; and if you have RAM to burn you can opt for the 64 MB CorePlus image which is the only one that starts up with wifi set up.
It's a kick to play with. It's just amazing how fast a minimal distro can be running out of RAM. Even when you load it up with Firefox and a bunch of other apps you're still only looking at a few hundred MB.
Linux is my main and the operating system I use (Laptop, Phone, Server and Media Center). It is fun to see other people trying to hack Linux to run on obscure or minimal systems but as a daily user I think the biggest achievement would be to run Linux more efficiently on a regular machine and not on obscure system.
It's not a great article.
Other people have mentioned Geexbox and XBMC which are useful media centre distributions.
Slitaz is a cool minimal distribution, with excellent internationalisation. (It's amazing what they fit in to such a tiny package.)
Tinycore / microcore are great minimal distributions, but I don't know how much they're being developed at the moment.
Exherbo looks suitable for masochists. (http://exherbo.org/)
Arch / Gentoo / Linux From Scratch are great for people who want to learn Linux or who know exactly what they want.