PC users who want to share their computer with another member of the household, or a house guest during the holidays, can download a free version of a software package that lets two people use the same computer at one time. The Desktop Multiplier software from Userful allows one computer to support up to 10 independent users. Each additional workstation requires it own monitor, USB keyboard, and mouse to be connected to the computer. "The free two-user giveaway doubles the utility and value of your existing computer with minimal cost," Tim Griffin, president of Userful, said in a statement. "In fact, if you already have an extra monitor and keyboard, it’s like getting a free computer for Christmas." The company said the software is in use in schools, libraries, hotels, and other businesses worldwide. It estimates that a 10-workstation system saves up to 15 tons of carbon dioxide emissions per year and reduces electronic waste by up to 80 percent. The free two-user licenses distributed under this promotion enable users with an extra video card (or a dual-head video card) to add an extra workstation. Users have obtained free two-user licenses and information about the promotion from http://userful.com/products/free-2-user. Two free downloads are available: a Live CD, which allows you to turn your PC into two independent workstations without affecting any of the software on your hard-disk, and one for users running Linux.