Before attempting this, please consult with the Ustream.tv terms of service.
- Navigate to the video stream that you want to download. (note that this does not work on currently streaming videos)
- Right-click “Open in popup window” and open the link in a new tab.
- In the URL, remove everything before and up to “&flv=”.
- Hit refresh and the file should start downloading.
Actually, there is a much easier way, just go here: http://ustream.tv/helpcenter/howto and look for “How to Convert Recorded Video Files to Different File Types and How to Download Them”
@CJ has the most recent working answer. Check his method here. Thanks @cj!