EtherTV allows you to create and share streaming video stations by aggregating videos from web sites like YouTube. Each station broadcasts the videos in a fixed order then repeats when all videos have been shown. Like broadcast television, anyone watching a station at a specific time will watch the same video, at the same location, as anyone else who is watching. However, viewers can choose to skip to any other video in the station any time they like. Viewers can also easily return to the current location in the broadcast.
If EtherTV doesn't fit your needs, you may want to try one of these similar (but completely unafilliated) sites.