A couple of months ago, I started researching putting a homemade CCTV system on the cheap. I picked up a D-Link DCS920 Wireless-G Internet Camera
The first approach I took was to setup an Ubuntu 9.10 box and install ZoneMinder. Ubuntu 9.10 has the ZoneMinder packages in the repository so installing it was not hard. There were some additional steps that I found here to get it up and running. On a scale of 1-10, getting ZoneMinder to run was a 6.5.
The trouble I faced was configuring cameras once ZoneMinder was running. ZoneMinder is a full featured application and multitude of configuration options was intimidating. I got it to run in a motion detection mode (where it will capture moving objects in the video stream) but was not satisfied with how fast it was capturing video. This was probably no fault of the software. The Ubuntu box was older box and may not have been able to keep up.
At this point, I was going to put this project on the backburner until I read a post on lifehacker. The Mac Mini that we use as our media server sits idle for parts of the day when we want a CCTV system in place. Thus there was no additional hardware costs. The resultant performance of the video capture with the Mac Mini was also leads me to believe that the Ubuntu box was too slow. The AMD CPU on the Ubuntu box is a couple of generations old where the Mac Mini has a more modern Core 2 Duo.
One nice feature of Vitamin D was the streamlined camera configuration process. It was able to auto detect the DCS920 wireless camera on our network and after clicking the "Continue" button a couple of times, we were ready to go.
By default, it records everything to the hard disk. It was straightforward to configure sending images of people to my email account.
The starter edition is free and so it fits perfectly into our budget. In the future, we might add additional cameras to our system (they have a compatibility list!) and upgrade to one of their more full featured editions.