Valve recently released their internal machinima editing tool, Source Filmmaker, as a free-to-the-public download and now some fans are claiming they've found references to Valve's unannounced next generation game engine, Source 2, tucked away within the code.
The original Source engine is the game development tool which Valve used to create Half-Life 2, Portal, and Team Fortress 2. Though it has served Valve well over the years, it has been in use since 2004 and is obviously getting a little bit long in the tooth. Many speculated that Valve had been working on a new engine which could potentially debut with Half-Life 2: Episode 3 and/or Half-Life 3 proper, but this is the first evidence that such an engine is in active development.
Fansite, ValveTime.net, claims to have uncovered several mentions of "Source 2" within the program files. ''Return an str with the current engine version," ValveTime quoted the files. "If key doesn't exist, assume 'Source', otherwise invalid -- assume next-gen 'Source 2'.''
Valve has proven considerable artistry when it comes to shaping the aged Source engine to their whims, but even they could use an upgrade once in a while. Valve has never publicly stated anything regarding a next generation iteration of the Source engine.