Hundreds cheaper than a Mac Mini, which doesn't come with a monitor
Want a one-and-done desktop computer solution for under $500? $474 after coupon: Dell Vostro 270 Mini Tower Ivy Bridge i3-3220, 4GB RAM with 21.5" E2213H LED Monitor
This bundle is the cheapest we've seen it, plus it's $129 off buying the desktop by itself. If you need a keyboard, this one's $10.