Webcam Security Software

Does anyone know of any webcam security software for Mac? Something that detects movement and takes a number of photos?

We've been having some trouble with nuisance neighbours recently and I'm a bit paranoid our house might become a target for burglary.

At the minute I'm using the trial of SecuritySpy. I was going to purchase it as £30 seems ok but I've got two webcams and for that I'd need the four camera license which is £80. That's just a bit too steep for me.