I saw a nice example for a communications agency (http://
www.carat.co.uk/) where an embedded video just played. Unfortunately
the video is no longer there.
The video was a wmv, or .mov, embedded with a plain old <object> so
accessibility on the technical side was poor, and there was the
horrible default video player around it.
However I really like the video. It was a video of their staff giving
one word explanations of what the company did. The video would cycle
through the staff, so I could hear what the company did quite clearly
and concisely and see a nice bunch of faces that work there. The video
was done quite well, in an apple promo style.
The other reason I liked it (at the instance) was the browser window
was in the background, and I was hearing what the people were talking
about, and that made me go looking for the tab it was hiding in.
Before I'd gone back to the site I knew a little about the company
from what I heard.
So technically, it was done badly (probably why they removed it) but
at the moment it worked for me and clearly communicated what the did
and didn't make me want to close the browser window / mute my sound. I
also found different people repeating the same word, or a different
word with the same meaning really hammered the message home.