If you do not have Windows Media Player, it can be downloaded free from Windows Media
MAC OS X
If you use a Mac with OS X 10.5 or later (older systems may work but haven't been tested) you can view the stream using the free and open source VLC Player. Copy this link - mms://octopustv-wmlive.wm.llnwd.net/octopustv_wmlive - and paste it into VLC Player.
(Media > Open Network Stream > Paste URL > Click Play / Stream)
The BBC also provide live coverage of the Assembly on their Democracy Live service.
For details of other ways to watch the Northern Ireland Assembly view this page.