Yeah, I was lead designer on Action Half-Life. The game we are working on now has it's roots in AHL. Glad to see there's still some name recognition.
I'll have to dig around and see what the Specialist guys are up to. Back in the day there was a bit of a rivalry between AHL and the Specialist and even the Opera. But I look back now and it's just kind of flattering that people liked our core ideas so much that they wanted to build their own games off it with their own ideas which is what the mod scene was all about.
The HL mod scene was where the most creative and innovative game design was happening at the time. I think as new distribution channels opened up like Steam, and game engines became accessible the mod scene has morphed into the indie scene. At least that's what it looks like to me having taken some years off game development. Now it's the indie scene that has the majority of the creative and innovative design. It's really great to see.