when streaming video, it can be quite hard to find a good balance between quality and a good connection. sometimes you are also confronted with bottlenecks by international connections.
video streaming seems most effective in workshops that do not concern software.

tools to check out:

vlc www.videolan.org/vlc/
theorure theorur.tvlivre.org/
quicktime broadcaster (propietary) www.apple.com/quicktime/broadcaster/
darwin streaming server developer.apple.com/opensource/server/streaming/index.html
wirecast (not free in any way) www.varasoftware.com/products/wirecast/
for max and pd users there are also several objects such as jit.qt.broadcast, see the usual repositories.

we did a workshop on this specifically:
xmedk.be/index.php?id=676