I'm using 2 each DLink 932BL models
You can download the MyDlink program or go to the Dlink site and download the Dlink Viewer
the MyDlink program has an android version for your tablet or smart phone so you can view what is happening while you are away from home.
It also lets the camera email like six pictures from the motion detection to a pre-set up email address.
The Dlink Viewer lets you set up a constant video surveillance/w motion detection or sound detection. However, it changes the User Account Settings on your computer, to allow for it to run all the time.
Currently I am running just the two ($109 for 2 at Walmart online), they are wireless, but you have to have a power cord to them, on setup you hardwire them to your cable modem and then after setup you can plug them in anywhere there is an outlet or you can run an extension cord to them.
I built a box out of lexan and aluminum for my front porch cam, they are indoor cameras but can work outside if they are covered.
they have a night view of about 15 feet (black and white) and daylight a clear picture (at 480 dpi) at about 25 feet color picture.
I am still experimenting with them, and want to head to radio shack to get some 18 guage wire to extend the length of power cable so I can run more than just two cameras.
Both programs allow you to run multiple cameras... Dlink will allow up to four... while Dview accepts up to ten... but you have to put in the ip addresses of each camera...
I'll make a post and keep it updated... I am ordering two more camera's next week... to make four.... then next month I will order two more... I have a laptop dedicated to the viewing program and an old external hard drive dedicated to the video capture. But that will change in the future as I learn more about the camera's and the programs.....
Sorry for the long post.... hope it helped...