Before blindly upgrading an entire office of existing PCs into the unknown, most IT departments will roll out one trial system to test the new OS. This preemptive step allows IT staff to check the OS in the existing hardware environment with the already bought-and-paid-for software. With Microsoft Windows 8, testing before a mass roll out is a particularly important step to ensure software compatibility. It's also a pretty crucial step to give yourself time to get acquainted with the drastic user interfaces Microsoft has imposed.
There are two ways to go about testing a new OS like Windows 8; 1) install the OS to a spare computer system and test away, or 2) install the OS to a virtualized PC. In this Beginners Guide, PCSTATS will show you how to create a virtual PC with Oracle VirtualBox v4.1.18 (it's free and very capable virtualization softare) and then install Windows 8 Consumer Preview to that virtual machine.
Slow computer got you down? Maybe a hardware upgrade should be in your cards, if so this guide to the Fundamentals of Upgrading a PC is an invaluable read. PCSTATS Tips