We always associate famous events (such as news, elections, sport championships, movie releases, and so on) to timeframes and personal memories. Consider the next movies Timeline made with ThinkComposer.
Sometimes we need to show multiple aspects or visions of a topic on various tracks of that Time road. Then a simple line is not enough and a parallel set of lines is required.
Plus, consider to show the timeline on the vertical axis.
Also, the amount of events to be displayed may be not dispersed on a regular basis, more when contrasting areas of time with almost no info against other plentiful of it. A way to overcome these inequalities is make timelines with non-linear shapes, for example using spirals, triangles or arcs.
Finally, you can see an interesting site about history of Timelines here.