The Watchport/V cameras integrate nicely with the environmental sensors. We already did a complete review of the Watchport/V cameras, which you can view here .
Up to four cameras can be attached to one computer, but a "multicam" driver has to be installed to use more than one. Unfortunately, Inside Out reports that there are some compatibility problems with Windows XP and the multicam driver. The driver refused to install (both normally and in compatibility mode) on two of our Windows XP boxes. We did get one camera to work, with the standard single camera driver.
Having separate drivers for a single camera and multiple cameras complicates the setup process. It would have been better to have a unified driver.
You can set the camera to snap pictures when a proximity sensor has been tripped. This is a great feature that cuts down on the number of JPGs you have to sift through to find something interesting.