Telerik have announced a beta version of a new product called r.a.d.Dock - ive tried the demo and it is very cool.

It allows sers to define dynamic layouts with simple drag-n-drop at design time and customize at run-time. Users can save this layout and later reload it again. A dynamic layout is built from dynamic objects (RadDockableObject) that can be rearranged on the client browser and special regions (RadDockingZone ) on the web page where these dynamic objects can be placed/docked.

The Quick Start Framework with Online Demos of r.a.d.Dock beta can be viewed at:
http://www.telerik.com/r.a.d.Dock

r.a.d.Dock beta installation is available at:
http://www.telerik.com/t3mp0m@t/2expire/RadDock_1_0_0_trial.exe