We have a streaming webcam in our Great Harwood shop. Just follow the link at the top of the
homepage.
It works through the wired internet connection at the studio- basically whenever anyone tried to open a web page at the IP address/port combination that we use for connecting to BT, the camera's built-in web server kicks in and displays the camera's homepage, one page of which is its streaming output. There's no computer needed.
It cost about £250, but needed an extra £50 to get power to it. As long as it has a decent upload speed, you can just hook it up to the ethernet port on your router and it works.
By default, ours is set to use low-res Motion JPEG as its codec, but if you run Internet Explorer you can get almost full-speed, hi-res video (if you're the only one connected) by using the MPEG-4 codec. You may need to accept the codec download from Panasonic to do this, though...
By all means pop in if you want to have a look at how it works...