<p>Application frameworks such as DotNetNuke, Eclipse, Websphere and so forth are available today which offer customizable frameworks that can be used as dashboard applications.  Do you use these or do you and your peers keep writing amazing, modular, maintainable dashboard frameworks which you support yourselves?</p>

<p>Are there any good web based, OS independent frameworks out there that you suggest using to build your own enterprise class infrastructure around?</p>

The one I use is Oracle Application Development Framework. It's a complete, fully supported framework, and Oracle use it themselves to build their own enterprise applications. It comes with a lot of JSF components that are very easy to bind to the underlying data objects.
I'd recommend this  for all Java applications that need database data.
You find a discussion of it on the Oracle Wiki:
http://wiki.oracle.com/page/ADF+Methodology+-+Work+in+Progressent