YouTube has created a Flash based application called Warp to browse through videos in a more visual way. Similar to DiggSwarm, videos are visualized as a network of strings and related videos appear when the user moves the mouse over the circular thumbnail.
Browsing through related videos is a very playful and entertaining experience. I can confirm that the interaction invites the user to dig deeper and get a bit lost in the material (being a web-user with a short attention span). Videos can be viewed directly in the Flash application without leaving the unfolded / developed network.
To start with a video simply go to http://www.youtube.com/warp.swf?v= and add the video ID. I haven’t come across a better way to start browsing for related content. If you have – please let me know!