Despite the fact that the work I do is not top secret, nor do I have any enemies, I have always felt safer and better protected with the presence of security cameras. You just never know what you might pick up. Plus, I often work late at night and my office is next to a bar, and since my car sits outside, I like to be able to keep an eye on it at all times.
I've toyed around with semi-professional security systems (the kind that have dedicated DVRs and indoor/outdoor camera with LEDs for night vision), and basic wifi cameras for my house. Neither produce very high quality video. If you need to analyze somebody's face or try to read a license plate, you're pretty much screwed. The best you can get is a description of what someone is wearing or the model of a car.
When I went to set up my office cameras, a buddy of mine
suggested using webcams. Typically we think of webcams as low-quality cameras that we use to talk to relatives or co-workers over Skype. But in reality, the quality of webcams have vastly improved in recent years. I've been using Microsoft's LifeCam, a 720p HD webcam for Skype, and am always being told how crisp and clear I look (and I'll take all the help I can get).
So I employed the same webcams for my security cameras, and they work great! The nice thing about these cameras in that they use a small footprint, and they are USB powered so you only need one cord running to it. Plus with USB extension cable with a built-in repeater
for $10, you can safely wire a camera from a good distance from a computer. And image quality is great even at night. These Microsoft HD webcams used to run around $79. I just picked up another one on Amazon
I use a recording program from DeskShare called Security Monitor Pro that costs $90. This software allows me to start recording on motion detection. It takes video clips, still picture, and can even email me the media or publish to an ftp server. I record my cameras at 10fps, which allows me to see enough action so I don't miss anything, while not overloading my CPUs.
Then at the core of it all is a dedicated Acer Aspire. I picked up this $500 computer from Fry's. It's loaded with an Intel i3 at 3.06GHz with 6GB of RAM and a 1TB hard drive. It's amazing how inexpensive technology is these days. I previously had a lower-end Dell recording, but it only had a single core and it choked when I tried to view and record two near-HD streams.
So for as little as $700, I have a security system that is computer-based, and actually records higher quality video than typical dedicated prosumer security rigs.
Like I said, this is a little over the top for my needs, but it's nice to be able to see my surroundings. If you're looking to set up a basic security rig, I definitely recommend going this route. Like I said, I've toyed with lots of possibilities, and since this system records high quality video with great features that lets me see what's going on when I'm away from the office, there are really no downsides.