Fedora, ubuntu, kubuntu, open-suse, backtrack, Mint... So many tempting linux distributions that you want to test (if you don't, don't bother reading the rest :p). Hopefully, all of them are legally available for download. However, you don't want to burn 10 CDs each month to test the latest releases. So how about booting from your USB drive??
Actually, this is possible, easy and practical. To do so, first you'll need to download the iso image of the linux distrubution you want to install on your USB drive. Now, download the Linux Live USB Creator open-source tool available at http://www..linuxliveusb.com .
Run it on windows and you'll see something like this:
The GUI (guided user interface) is easy to use. Just select you USB drive, the source of the iso file and the space you want to dedicate for "persistance". "Persistance" is one of the coolest features in Linux Live USB Creator. It allows you to store the modifications and settings that you performed on your live distribution directly in you USB drive.
Now, just click on the lightening and your live USB is created :)
For the time being, you'll need to configure the boot order in your BIOS so that you can boot from your USB drive. In case you don't know how to do that, I recommand the following tutirial:http://www.whitecanyon.com/esupport/index.php?_m=knowledgebase&_a=viewarticle&kbarticleid=7
Well, everything is now set up for you to boot from your USB drive. But that's not it: you can also run your Linux distribution as a "virtual machine" inside windows! To do so, just execute VirtualBox\virtualize_this_key from your USB drive.
Hope you enjoy it :)