Yubikey is a new two factor authentication system. One of it’s really appealing features is that they keys can be bought really cheaply. At a wholesale price of $25 per a key with discounts when you order in bulk. Besides the great price yubi keys are very flexible in easily being able to easily build two factor authentication into almost any application. yubico has a great deal of documentation on their website. Yubikeys are designed for generating encrypted one time passwords. There is no battery in Yubikeys so there is no battery to die, what is a good thing. Yubikeys are also very durable, while the second version of Yubikeys are even more durable then the first version.
How it works is you stick the Yubikeys into your USB port and push the center button where you see the green ELD in the last picture. The light will go out while you push the button. Once you push the button Yubikey transmits a 44-character string and then send a new line command (enter). This is all very easy to use because the Yubikey shows up as a keybord to the computer so it will work for any computer. It is even possible to get it working on your iPad with a little adapter. The possibilities are pretty endless, so please let me know what ideas you have, and how you have been using the Yubikey.
I have included a bunch of pictures of the yubikey below showing what is included in the package that you get when you order a yubikey. I ordered 2 YubiKeys (1 Black + 1 White).