3D Games Maker Software Free

Have you ever dream of creating your own 3D game for free ?

Game creation is a long and complex processus, you need a good idear, moddeling and texturing techniques, level design knowledge and some script writing competences. Probably you'll have to share your competences and knowledges and distribute work with some other friends.
Finally you have to find the right tools to create, manage, test and distribute your game.
There are many, many commercial 3D game engines wich can help you reaching this goal, some are available at a reasonnable cost, but some are really high priced.
Fortunatly  there are also a bunch of FREE 3D game engines and development kits you can use. And it's not because they are free, that they are not good !. Some of the best modern game engines and dev kit are available for FREE. (Idtech4, CryEngine3, Unity or Unreal development Kit for example)
Here is a list of the 18 major Free game engines you can use to create your games. Some are all purpose game creation, some are dedicated to specific type of games (isometric, FPS, RTS, Flash) but all of them have a very large user community, many forums, free utility tools, information blogs and tutorials to help you starting from nothing.
This list is not totally completed, so feel free to tell us about a free game engine you could have miss !
Complete listing after the link.

3D RAD

3D Rad is a freeware development tool used to create 3D games, interactive 3D applications and physics-based simulations for Microsoft Windows XP/Vista/7. Works created with 3D Rad can be delivered to the final user as stand-alone applications or web-based applets.
Specifically designed with computer graphics artists and non-coders in mind, 3D Rad aims to provide the simplest developing workflow possible, without sacrificing flexibility. The editor is based on a collection of components (called 'objects') that can be combined and configured to interact in various ways. Without writing any code, goals like opening a door when a character approaches or avoiding obstacles with a car while following a race track can be easily achieved.
Homepage: http://www.3drad.com/
type : 3D game dev tool
plateform : Windows
Required level : Beginner

Aleph One

Aleph One is the open source continuation of Bungie's Marathon 2 game engine. Available for Mac OS X, Windows, and Linux, Aleph One supports Marathon 2 and Marathon Infinity natively, and Marathon through a fan-made conversion. Many third party scenarios and net maps are also available.
It's now a very old game, and a very old 3D egine but it still have a large fan community !
Aleph One is available under the terms of the GNU General Public License (GPL).
Homepage: http://marathon.sourceforge.net/
type : 3D game dev tool
plateform : Windows, MacOSX, Linux
Required level : Beginner

ARdor 3D

Ardor3D is a scengraph based 3D game engine, written entirely in Java and utilizing OpenGL for high performance gaming and visualization. He is a professionally oriented, open source, Java based 3D engine.  A tool to create better real-time 3D games and simulations. Ardor3D was quickly adopted by several companies, independent game studios, and government agencies.
Homepage: http://ardor3d.com/
type : 3D game dev tool
plateform : Cross-platform
Required level : Beginner

Away3D

Away3D is a realtime 3D engine for Flash in ActionScript 3.0. Started in 2007 by Alexander Zadorozhny and Rob Bateman. The engine is Open Source under the Apache 2.0 license and is free to use for any purpose, also commercial projects. Away3D can be used to render 3D models and perform various other 3D computations, Import/export of several popular formats, including animated meshes
Away3D is also the only Open Source 3D library for the Flash Player that is still actively maintained and keeps adding support for new features and new Flash Players
Prefab3D companion app
Written in Adobe AIR, this companion app provides a visual interface to many of the most advanced Away3D features such as the generators, but also adds a bunch of tricks to your arsenal such as visual tweaking of UV maps, path editing, optimization and error checking of imported models, export to several formats (including AC3D) and it even has a a live connection to your Flash file, so you can export and play with geometry created at runtime.
Homepage: http://away3d.org/
type : Flash 3D engine
plateform : Windows
Required level : Intermediate

CAFU

The Cafu Engine is an all-purpose, modern 3D graphics engine and game development kit, feature complete to get you started quickly.
Cafu is available to everyone as 100% free software under the GNU General Public License (GPLv3). It can be used to create a variety of 3D applications, including games, simulations, and training and architectural software. Written in C++, the tools, libraries and framework have been designed to make the development of new games and other 3D applications easy. They are actively and continuously developed in order to provide the latest technology.
Cafu includes a graphical editor, CaWE, that contains all the tools required to create new levels: a Map Editor, GUI Editor, Font-Wizard, Material Browser and Model Editor.
Homepage: http://www.cafu.de/
type : 3D game dev tool
plateform : Windows, Linux
Required level : Intermediate

Cube 2 Sauerbraten

Cube 2 is a Quake like game, but it integrate authoring tool in-game !
The game features single-player and multiplayer gameplay and contains an in-game level editor, its main feature. The engine supporting the game is entirely original in code & design, and its code is Open Source.
Level editing has never been so much fun: a press of a key allows you to modify the geometry / textures / entities in-game, on the fly. Even more novel, you can make maps together with others online, in the unique "coop edit" mode. It use a unique "6-directional heighfield deformable cube octree" world structure that is the basis for its in-game editing. Occlusion culling, pixel & vertex shaders, very accurate lightmapping, robust custom physics system, network system, models, sound, scripting...
Homepage:  http://sauerbraten.sourceforge.net/
type : Game Engine
plateform : Windows, Linux, Unix, Mac OS X
Required level : Beginner

CryENGINE 3

The CryEngine 3 is now free of charge for non-commercial use. The award winning SDK provides the complete game engine to create AAA quality next generation games for PC, and includes the CryENGINE®3 Sandbox™ level editor, a production-proven, 3rd generation “What you see is what you play” (WYSIWYP) - tool designed by and for professional developers. The free toolset is available for download at crydev.net.
An impressive app, one of the best if not the best graphical engine on the market.
Homepage: http://www.crydev.net/
type : 3D game engine & SDK
plateform : Windows
Required level : Intermediate

Delta3D

Delta3D is a widely used and well-supported open source game and simulation engine. Delta3D is a fully-featured game engine appropriate for a wide variety of uses including training, education, visualization, and entertainment. Delta3D is unique because it offers features specifically suited to the Modeling and Simulation and DoD communities such as High Level Architecture (HLA), After Action Review (AAR), large scale terrain support, and SCORM Learning Management System (LMS) integration.
Delta3D is an Open Source engine which can be used for games, simulations, or other graphical applications. Its modular design integrates other well-known Open Source projects such as Open Scene Graph, Open Dynamics Engine, Character Animation Library, and OpenAL. Rather than bury the underlying modules, Delta3D integrates them together in an easy-to-use API -- always allowing access to the important underlying components. This provides a high-level API while still allowing the end user the optional, low-level functionality.
Homepage: http://delta3d.org/
type : 3D game dev tool
plateform : Windows, Mac OS X
Required level : Beginner

DXStudio

DX Studio is a complete integrated development environment for creating interactive 3D graphics. The system comprises of both a 
real-time 3D engine and a suite of editing tools.  Using DX Studio you can build complete real-time interactive applications, simulations or games, for standalone use or for embedding in other Microsoft Office/Visual Studio applications. DXStudio is distributed freely but you can upgrade to the next higher license by just paying the difference in price from your current version to the new version. For example if its $50.00 more for the next higher license thats all you pay.
Homepage: http://www.dxstudio.com/
type : 3D game dev tool
plateform : Windows
Required level : Beginner

Game Blender

The Blender Game Engine is a component of the leading open source 3D App : Blender, its a free and open-source comprehensive 3D production suite, used for making real-time interactive content. The game engine was written from scratch in C++ as a mostly independent component, and includes support for features such as Python scripting and OpenAL 3D sound.
It uses a system of graphical "logic bricks" (a combination of "sensors", "controllers" and "actuators") to control the movement and display of objects in the engine. The game engine can also be extended via a set of Python bindings.
Homepage: http://www.blender.org/
type : 3D game dev tool
plateform : Windows, Linux, Mac OS X.
Required level : Advanced