Four Linux Live CDs, The Executive Summary
prostoalex writes "ExtremeTech published a review of 4 Linux live distributions that do not require installation and run off a CD. Knoppix, Feather Linux, Gnoppix and MEPIS Linux were researched, with Knoppix winning the competition (and Gnoppix not graded, since it's still in beta)." One more (of the seemingly infinite number of live distros) I've recently tried and been happy with is called Slax, and is what it sounds like -- a live Slackware distribution. Slax worked great with my finicky older Toshiba laptop. (However, slax.org appears to be down.)
The article only seems to mention using these distros as a means to introduce oneself easily to Linux. While this is an obvious use of Linux-on-CD type distros, it's by no means the only one. Personally, I've found these things to be fast enough for the difference to be barely perceptible from proper installs.
I've been using Knoppix for a while now and have found it to be really rather awesome. The possible uses are almost limitless and this will improve even more if the ability to write to NTFS volumes is ever introduced.
For example: Recently a friend managed to fuck up his Window XP install beyond repair. I burned him a copy of the ISO and Knoppix sorted it out in minutes. It's blisteringly fast, the hardware auto-detection has to be seen to be believed and the amount of software on that one disc is mindblowing. It's certainly worth keeping a CD copy handy...
However, I'm intrigued as to why MandrakeMove wasn't included in the article. I much prefer to use Knoppix because of its ability to mount hard drives, but MandrakeSoft have been very perceptive in their implementation of USB keys. By carrying around configuration options and personal data on a USB storage device, anyone equipped with a MandrakeMove disc can convert any CD-bootable PC around the world into an equivalent of their home desktop. Many people have predicted that this could become a lot more commonplace in the future where computer users would have to rely a lot less on a home workstation-centric lifestyle. I haven't investigated, but I would guess that persistence can be gained in Knoppix by somehow copying the contents of the ramdrive somewhere more permanent.
Turkeyphant
I got a copy of sun's java desktop from the linuxworld expo. It is basically a gnome desktop that boots from a CD; not too bad although I haven't played with it much.