At a press conference this morning at GDC in San Francisco, Epic's Tim Sweeny has just announced an entirely new way of doing business with the Unreal Engine. The new model provides full access to the engine - including the complete source code of the game - for US$19 per month.

While individual licenses can still be negotiated (and will need to be in the case of console games), this means that anyone making a game - from single person indies to large scale companies - can now harness the full power of the Unreal Engine. Epic's take will simply be a flat 5% royalty fee on gross revenue (including revenue made from game sales, in-game advertising or other in-game sales like virtual property).

The source code will be made available on GitHub for subscribers; Mark Rein noted after the press conference that it will be under its own "Unreal Engine 4 license", and that it is not an "open source product".

This announcement was accompanied with a demonstration of the Unreal Engine 4 editor - it's been a while since I've seen any of the back-end tools used to make games, but this thing is frankly amazing and hopefully we'll see a video of this shortly.

Tim Sweeney has also made an announcement on the official UE blog with a little more information.