TimeTube is one of those rare YouTube mashups that make the video-sharing site both fun and functional. Type in a search term, and TimeTube lines up the results on an easily-navigated timeline, letting you trip down memory lane or learn more about a topic as it progresses through the social media jungle. There are alternate views—a list, a flipbook, and geo-located—but the timeline view is what really sells this mashup. Got another tool that stramlines and organises YouTube searches? Let's hear about it in the comments.