Here are some of the more interesting links I have to share:
Knoppix - www.knoppix.net - Are you interested in trying Linux, but you do not want to mess-up your current configuration? Then Knoppix is for you. This is the only zero installation, full Linux distribution. All you need is a CD burner, and you can create a bootable Linux CD. This is also great to use when you are borrowing a friend's computer. Everything is done in RAM. If you use rsync with freeshell.org, you do not even need to save files locally. You can even run Windows' programs with Wine and edit your office documents with OpenOffice while running Linux.
SDF - www.freeshell.org - Who says you can't get something for nothing. How about a free Unix account on someone else's machine? What a great way to learn Unix. All you need is telnet to sign-up for a free account. Just because I'm in a generous mood, you don't even need that. You can login from a Java applet at http://docbill.freeshell.org/telnet/.
coLinux -- www.coLinux.org - Thanks to Knoppix, you fell in love with Linux. But you still need to run Windows most of the time? Well thanks to coLinux you can run both at the same time without loss of performance. Oh, and don't forget to checkout coLinux Tools.
BusyBox - www.busybox.net - Now that you got your Unix fix, how about an emergency boot floppy, or Linux on a really small device. Having created my own mini-Linux distributions in the past, I know when to cry uncle. If it is small, and it's Linux, it should be built on BusyBox.
Fedora - fedoraproject.org - Do you want to use the latest and best Linux has to offer? I suggest giving Fedora a try. This is the distribution most Linux professionals use at home.
Red Hat Enterprise Linux - If you want to run Linux profressionally, Red Hat Enterprise Linux is your best option. Not only does Red Hat provide world class support, but they offer professional training and certification. If you just want to give it a spin, without paying for support, take a test drive on CentOS. Of course CentOS is not the same as Red Hat Enterprise Linux, but CentOS is built from Red Hat Enterprise Linux source code.
Cygwin - www.cygwin.com - Hey, didn't Bill Gates claim that Windows NT is Unix? Why do I need all this Linux stuff anyway? Well. Errh. I guess you don't. But you definitely need a suite of Unix-like tools if you want to use Windows as Unix box. Cygwin is great both for the professional programmer and the person just starting out trying to learn Unix. If you have an extra two gigabytes of disk space to spare, I definitely recommend giving Cygwin a try.
Celtic Knotwork Designs - This is where I found most clip art used on this site.