Is not really intuitive how can you add a reference to a css stylesheet at runtime in ASP.NET in the HTML head section: you need to call the page's ClientScript manager and register a Javascript script block defining your script code as a link tag. Remember that RegisterCssReference method will only work if you call it before the page's OnRender event method, so use it in OnLoad and OnPreRender page's events.

Why should you pay for a chart program if you can geti it for free?
Autodesk published an impressive web application completely free to let you draw you own charts online.  Project Draw allows you to do everthing you need:

http://draw.labs.autodesk.com/ADDraw/draw.html

You don't need to have a product serial number to use all the features: just create an account and skip the last step where you are asked to provide the key:

 https://registeronce.autodesk.com/eidm/selfcare/beginSelfRegistration!input.action

Don't forget to register and press ctrl + d once you have visited the link

If you are considering to use Mootools javascript framework, and you need to see it in action, visit

 http://demos111.mootools.net/

to obtain immediatly cool effects and the relative sourcodes.

Immagine a scenario where you need to handle how a browser should open different urls into your site. You need to open every link into a new browser's window except links to documents, to avoid opening a blank window.
Infact, using the attribute 'target' into an anchor: 

will open first a new window, and then let you download the file.As you can see  this is not a good solution for this scenario.
Here you can find a simple Javascript that will resolve this kind of problem