There are a number of extensions to Objectify developed by third-parties. This wiki will need to be updated if/when these projects are migrated elsewhere due to Google Code's demise:

This is a plugin that provides support for Objectify in Gaelyk applications. Gaelyk is a toolkit for using Groovy on Appengine.

http://code.google.com/p/gaelyk-objectify-plugin/

A plugin which integrates Objectify with the Play framework:

http://code.google.com/p/play-framework-objectify/

This is a sample application that provides fulltext search using Objectify:

http://code.google.com/p/fulltext-search-in-objectify/

This program generates concrete, typesafe java classes that let you query for entities without relying on text strings to identify fields. For example, you would use filterByColor("red") instead of filter("color", "red").

http://code.google.com/p/objectify-query/