>Btw, I have seen references to Infragistics NetAdvantage here but know nothing about it. Is it a framework too?

Hi Dmitry... me again. :)

Infragistics (DevExpress and others) is a great collection of components, which gives your applications instantly professional look and features. There are win and webforms components, controls, ready to be used.
You might visit their website (www.infragistics.com) and check some of these functionalities... have a look at the "NetAdvantage for .NET" suite of controls.