Select following from Menu : File -> New... -> Other...
click on "Next >"
Enter Project name required for the project, in following dialog box :
click on "Next >"
If you want to run the project in standalone mode then, Select "Yes" for "Would you like to create a 3.x rich client application?"
click on "Next >"
Select "RCP Mail Template" (if a demo project has to be created )
click on "Finish".
Now, to run the project, right click on the project and select, "Run As" -> "Eclipse Application"
Following screen will be visible, when the demo app will run: