Unreal Development Kit

The Unreal Development Kit (UDK) can be downloaded and used to make games using the Unreal Engine 3. However, there is a licensing fee if you release the games for profit which is supposed to be affordable even for independent developers.

November 5, 2009 - "Epic Games, Inc. announces the launch of the Unreal Development Kit (UDK), a free edition of Unreal Engine 3 that provides community access to the award-winning toolset like never before. This software release is available to anyone interested in using 3D game engine technology, including game developers, students, hobbyists, researchers, creators of 3D visualizations and simulations, and digital filmmakers. Anyone can start working with the industry-leading Unreal Engine 3 toolset by downloading UDK at www.udk.com, where detailed product features, technical documentation, commercial licensing terms, support resources and more are also available.

An unprecedented milestone in game development, the release of UDK awards free access to the same world-class tools and technology used by many of the world’s best video game developers and publishers. Unreal Engine 3 is a constantly evolving game engine, and UDK contains all the most recently added features and technological enhancements, including many that have yet to be seen in an Unreal Engine game. Furthermore, Epic Games will release ongoing, upgraded builds of UDK for free.

There is no charge for noncommercial or educational use of UDK. Over 100 academic campuses currently use Unreal Technology as part of teaching game development-related courses, and colleges with plans to incorporate UDK into their curricula include the University of Pennsylvania, North Carolina State University, The Art Institute system of schools, Drexel University, Westwood College, DeVry University and Atlantic College, with many others to be announced.

Individuals and companies wishing to develop software for commercial purposes should refer to licensing terms at www.udk.com/licensing. Commercial terms have been structured to make it easy for independent developers, start-up firms and seasoned professionals to use UDK with minimal financial barrier from concept to deployment. UDK is currently for PC use only, although console support is under consideration. Developers approved to make games for Xbox 360® and PLAYSTATION®3 may inquire for more information by emailing udklicensing@epicgames.com."

[Source: udk.com]

They even have a 74 page PDF document on how they created a simple game called Whizzle (vertical scrolling puzzle game) using only the UDK.