For designing and controlling the page flow through an application, Java-based platforms can take advantage of Struts, the Beehive NetUI stuff, Spring Web Flow, and numerous other frameworks and models.
For a long time, this capability was not well supported in ASP.NET. Now, it is. Matt Winkler at Microsoft just sent around a note describing a project he just delivered. It employs Windows Workflow Foundation and a page-flow designer to model and manage the page-based navigation in an ASP.NET app. This model-based approach allows developers to keep complexity low, even as navigation options become more complex. It doesn't make sense where people can navigate "freely" through the site, as in some websites and portals. But where navigation needs to be constrained, this page flow designer can help greatly.
Here's an example page flow model from the designer :
The sample ships with providers for both ASP.NET as well as WPF. Matt has more details on his blog here.
Download the bits here.