Hi Grant-
None that I am aware of. However, you can restrict the use of applications
which users use that may utilize streaming media.
One method for that-if you know the application(s) you would like to
restrict- is by using software
restriction policies in a group policy which is linked to a container the
users accounts are in.
User Configuration->Administrative Templates->System->'Don't run specified
Windows applications' is the setting. Just enable the setting and add
the names of the applications there as the restricted applications.
There are additional options in Server 2003 for application restrictions as
well, including the ability to create a hash of the application's executable
as a more certain restrictive measure.