This week I ran a workshop on mind mapping, brainstorming, and timeline creation. These are the timeline creation tools that I included in the workshop.

Meograph offers
a nice way to create narrated map-based and timeline-based stories.
Much of what Meograph offers can be accomplished in Google Earth.
However, Meograph is browser-based so that students can create stories
even if they cannot install Google Earth on their computers. August 2019: This tool is no longer available.

Dipity is
a great timeline creation tool that allows users to incorporate text,
images, and videos into each entry on their timeline. Like most good web
tools, Dipity has a collaboration option and has multiple options for sharing your timelines publicly or privately. Each entry to a Dipity timeline
can include multiple types of media which allows users to add more
detail and information than can be included in a traditional timeline.
If you want to import Tweets and other social media messages, you can do
that too on Dipity. Dipity will work on your iPad. This tool is no longer available (August 2019)

myHistro is
a timeline builder and map creation tool rolled into one nice package.
On myHistro you can build a personal timeline or build a timeline about a
theme or event in history. Each event that you place on your timeline
can be geolocated using Google Maps. myHistro timelines can be created
online or you can use the free iPad app to create events on your
timeline.

I like XTimeline because I find it to be a great service that is very accessible to high school students. Using XTimeline students can collaborate, just as they would when making a wiki, to build a multimedia timeline. Timelines built using XTimeline can include text, images, and video.XTimeline will accept dates in A.D./B.C. format. Update 1/20/2014: XTimeline appears to have gone offline. 

TimeGlider offers
some nicer layout features compared to XTimeline, but is not quite as
intuitive to use as XTimeline. The layout features that I like about TimeGlider is the ability to stagger or indent events below each other in a sequence. TimeGlider also
makes it easy to display the relative importance of an event by
increasing its size in comparison to other events on the timeline.

Time Toast is
easy to learn to use. Time Toast does
not have the more advanced editing options that XTimeline and
TimeGlider offer.