BYOKVM
Larry Magid of the New York Times points out yet another low-cost way of
sharing a PC monitor with your Mac mini: use a KVM switch. For about $50 you can snag a device that will let you easily switch back and forth between a Windows PC and your Mac mini (or any other Mac, for that matter).
If VNC is not your thing, and you don't need or want to acquire an extra monitor, mouse and keyboard for your mini, a KVM switch is a great option. It's also the more user-friendly route if you're buying a mini for relatives who already have a Windows machine and are wary of leaving it behind completely.
Has anybody used this option to set up a new mini for one of their familial or friend "support clients"? ;)