With Chris broadcasting the break on Ustream in order to allow for recording the breaks on YouTube, there have been a lot of complaints about the ads on Ustream constantly interrupting the viewing. A couple of months ago, I got a new computer, and when Best Buy converted over all my old files, the Geek Squad rep also installed AdBlock in conjunction with my browser (Google Chrome). Since that was done, I no longer get ads when I watch Ustream broadcasts.
I'm not much of a computer expert, but I would assume that there are similar products for other browsers.