Arqade and Scifi both allow embedding YouTube videos by posting the URL on its own line. I think there is use here for this as well, as long as the moderators and high rep users police the content and make sure it's relevant (which is no different from embedded images). Given that anime is a video medium, it seems rather relevant for us.
I recently asked a question, Is there any explanation for "Tequila" in the Kuragehime eyecatch?, which I linked to a 6-second YouTube video. It would be much better if the video were embedded so that people wouldn't have to open a new page just to watch the video.
There was support for this on the Area51 page, but it never happened. Can we get this turned on?