This deal has ended.
Dell Small Business has their Vostro 200 Desktop for only $499 after $310 in instant savings. This is a well-configured machine and relatively inexpensive if you want to upgrade (just scroll across the component icons at the middle of the landing page). It comes standard with a 2.2GHz Intel dual-core processor, 1GB memory, 320GB hard drive, 16x CD / DVD burner, Windows XP or Vista Home Basic (I recommend XP, Vista isn't perfected yet), and a 20" LCD monitor. Shipping is free and sales tax is charged in most states.