While there’s been no news from Valve about any more Half-Life related games, fans are taking it upon themselves to expand the universe’s story. Prospekt, a sequel to the Half-Life: Opposing Forces expansion, is coming to Steam on February 11th with Valve’s blessing.
1999’s Opposing Forces followed U.S. Marine Corporal Adrian Shephard as he went to the Black Mesa Research Facility on a secret mission, and caught occasional glimpses of Gordon Freeman. Prospekt follows the same character as he goes to the Nova Prospekt prison, which was featured in Half-Life 2, to help Freeman, who has been overrun by the enemy.
Prospekt creator Richard Seabrook promises a "substantial, highly-polished and totally new addition to the Half-Life 2 universe." It seems like Valve agrees as it hasn’t shut the project down and is allowing it to use the Half-Life 2 license and art assets.
Prospekt will be released on Steam on February 11th.