The new SharePoint 2010 tools in Visual Studio 2010 have lots of options for extensibility and Wouter van Vugt has been working on some great extensions for developers. The tool can be downloaded from here. He has included:
* Sandboxed Visual Web Part Designer
* SPMetal integration in Visual Studio for creating Linq to SharePoint proxys
* Some Quck Deploy Steps in SharePoint Solution Deployment
It is on beta version but seems very useful.