Ark Linux's lecture on what a live CD is for.

From their news item on the main page, "Ark Linux 2006.1-rc2 and Ark Linux Live 2006.1-rc2 released"

About Ark Linux Live
Ark Linux Live is a "Live CD" version of Ark Linux Home, meaning it can be booted directly from the CD, without needing installation.
The primary uses of a Live CD are:

• Recovering a normal system after a big hardware or software failure (Ark Linux will launch a special live CD for this purpose later, with more recovery tools and fewer other tools)
• Checking the system out without any risk
• Showing others what Linux is like, on their own hardware
• Taking your favorite operating system with you - e.g. to get on the net with Linux even if you're on vacation and the only internet cafe in town is a Microsoft shop

While it is possible to use Ark Linux Live as your primary operating system, that is not recommended -- a live CD is always slower than an installed system because CD/DVD drives are slower than harddisks, and the compression needed to fit 2.5 GB of data on a CD takes up processor time. Use Ark Linux Home instead.

Ah, but what if that internet cafe is one merely offering a wifi spot, and not ethernet cables all over the place? What do you do with your Ark Linux live CD? nothing. Because you'd have to remaster the CD to take something off and put madwifi on it. Go figure.