An inexpensive solution as a first time experiment with a security camera and DVR card.
Camera - Swann Bulldog outdoor camera - 1/4 CCD, 420 TVL, 510x492, 12 LEDs - $77.
Q-See 4-channel DVR PCI card - $80.
So for $157 I can experiment with a camera and DVR card and see what happens. I can always...