Thomas Knierim created Scala Pages SCP a very thin web framework based on Scala and Java Servlets.

While this was fine it lacked a couple of thing. First of all a MVC pattern implementation ala Rails, Grails and ASP.NET MVC. Also template extension wasn't implemented, as well as internationalization.
But I was looking for a thin Java VM based web framework that a could use for future development. So I used SCP as a base and extended it with the following features:

• MVC pattern implementation as in Rails, Grails, ...
• internationalization
• a Flash scope that can hold variables over a request
• template extension to be able to have a base template and extend from it.

There are many thing to improve. The template extension for example is not able to add to head or body components. Documentation is lacking as well.

All in all however it is useable, fast, very thin and can be combined with any other framework. Meaning the user is not bound to anything like in Grails or Play.

SCP.MVC is hosted on Launchpad.