The popularity of webcams have grown quite a bit in the last few years. This could possibly have to do with cheaper digital cameras being available, as well as bandwidth and quality web hosting.
Recently, a trend has been going toward webcam portals, which are collections of many other peoples webcams, where the adjacent camera subjects interact with each other.
There seem to be two popular windows webcam applications:
Webcam32: http:/www.surveyorcorp.com
and, ConquerCam: http:/www.conquercam.com