I'm searching for a Javascript library to create line charts like the ones of Google Analytics. When the mouse is over a point, a box shows you the data.
An example is at http://wikirank.com/en
No Flash or Air, only JS and client-side Canvas...
Better if Free...
Edit: If you want a free library, try Flot.
Emprise Charts is a commercial library that I've seen featured on news sites.
There's JS-Charts which looks pretty awesome.
Or, if you fancy rolling your own you can create your own charting component using this library...
Another option is to use Google's visualization APIs.It's pretty easy to use, and they have a several options for displaying data. One thing to keep in mind is some of the visualizations require you to send your data to their server, though none of the canvas/svg ones have this requirement.
As an alternative to Flot, if you are using Prototype.js as JS framework, you can use Flotr.
Dojo also has something similar, though the example shown doesn't have similar functionalities but can be implemented to behave like the one you want,