Knoppix is a complete operating system that runs from a cd or dvd disc, it runs in your computers ram and doesent alter or move your files on the hard drive, basically you put the knoppix disc in your cd-drive and reboot you computer it will then automatically start up knoppix, it only takes 3 or 4 minutes to get started and then you can play around with it , it is safe because it doesent alter your files, and it is helpfull like when your windoze isn't working, it has tons of builtin goodies like a cd burning program, media player, open office , Gaim messenger, gimp , and more. if your interested the best part is its free and heres a link ojn this page you can download a cd version or the newest dvd version and give it a try.

http://distrowatch.com/index.php?distribut...th=all&year=all

this thing saved my ass once..

Mr. Nest's laptop harddrive went dead, and we couldn't even start windows.. seriously if we reset the computer, it would go past the DOS prompt, and then as soon as it show the starting screen for xp, it would either sit there for a long time and then rest after an hour, or it would just reset instantly.. so with the option of formatting the harddrive hanging over us, he thought of something.. he popped in the knoppix disk, and then he took his old xbox hard drive.. (the 40 gig i gave him) and then he formatted it in FAT.. which by the way, is the ONLY windows-compatible file system that can be read by linux.. and then he pluged it into this IDE to USB adapter, and plugged it in to the laptop.. so right now, as i type this, i am moving files over to the 40 gig harddrive.. oh yes and apparently, the latest version of knoppix allows you to make storage devices writable with a single click.. before that, you could only read, not write to the harddrive.. so yeah.. needless to say, KNOPPIX saved my ass..

Seems like it'd be pretty reliable since it uses some programs I'd recommend as alternatives in case your primary is taken down.