i.e. importers, map editors, shader editors, etc.
MonkeyWorld3D is our humble try to bring a new methodology for making games in Java using jME(Java Monkey Engine). Our aim from the beginning is to make a (What you see is what you play game editor), while we have managed to up reach some milestone versions of the editor, a lot more still needs to be done to complete the job, and we hope that MonkeyWorld3D bases this trial, and hope that some great games will be done using it.
We also tried to get some clean model for the game in general, where we dealt with Entities only, which might be the basic part of any game, and extended stuff as we seen suitable. We also added some components which are very frequently used in any game, for example, environment tweaking, like editing the Fog, World lights, Sky box and other type of editing which will normally occur in a game level.
The level designer can add primitive entities like for example Boxes, Spheres, etc. There also exist more complex type of entities, which will be jME(Java Monkey Engine) models and also entities such as global triggers. Global triggers will be responsible for executing user deffined scripts.
We also made management of the workspace extremely easy to the user. The user will start of setting a workspace on his local disk. Then all resources imported to his workspace will be saved to that location. There are a few supported model formats that can be imported and among them are the 3ds, obj and md2. Once these models are imported, they will be converted to the .jme format.
Each entity will have a level of settings. Some of which are the most commonly used, for example applying a texture on the entity or transforming the entity to the designer~Rs request. Then there also exist some more advanced settings, for example, setting that entity to emit light, or adding a sound effect to the entity.
We also developed a gizmo controller, which will allow the user to control entities in the level at runtime. The user will be able to drag any entity to any location in the level. A user can also set some camera specific settings, like making the camera stick to the terrain or letting it run freely around in the level.
All this can be used as a stand alone game application where you don’t need the editor to use it. Also, introducing the entity concept in the game will shift game development, in a more specific, more game oriented environment.
Currently the levels will be saved to xml format and this will allow the game coder to load the levels into the game framework and interacting on these levels.
from MonkeyWorld3D site
In jME directly there is also a particle editor, model loader (that can be used programmatically or via direct execution) that can load, display, and even convert models, and various other miscellaneous editors.
Also, there is the GameConsole that has jsr223 support for scripting. You can see a video I created a while back here:
http://www.jmonkeyengine.com/jmeforum/index.php?topic=4761.msg38180#msg38180
…and I’m sure there’s a bunch of other stuff I’ve completely missed. :o
Model loading we’ve tried to focus more towards standardizing on Collada (although we still support other formats) and our binary format tries to support as much functionality from Collada as possible.
BTW, we just released jME 1.0rc1. 
Some codec that I don’t have - refuses to play :(.
Actually, it’s doing that for me on this machine as well. :
Not sure how I encoded it but I guess I did a crappy job. :o
plays fine here… this is all Info I was able to get from it: Video: XVID 640x480 25.00fps 117Kbps [Video 0]
Eh… it’s just XVID. One of the most popular codecs out there.
You can use VLC to watch it… or you can install the xvid codec (or ffdshow tryouts).