Google Calendar / Ajax / Dojo Toolkit
OK, so I took a closer look at Google Calendar's event creation UI and I think it would be perfect for a timeline / sequencer UI. Take a look at this screen capture and compare it to the timeline you get in PowerPoint producer.
Now, also look at what the Dojo folks are doing with their Dojo toolkit. This thing is pretty slick.
http://dojotoolkit.org/dojo/tests/widget/test_Layout.html
Look at the code for it. There is almost nothing. They just utilize custom HTML attributes and process them with JS behind the scenes to hook up all the behavior and event handlers.
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