About ooooh 6 years ago... When Valve brought out the epic
Half Life 2 they included a nifty little version of the original Half-Life, but with added niceities from the new Source Engine they used to make HL2. This meant that you now had translucent water, and nice ragdoll physics, so that a bazooka would actually send people flying up in the air rather than them simply falling over dead.
Sadly HL: Source was nothing more than the original game (bereft of any improved graphics) and failed to meet expectations.
So a bunch of budding modders decided to do what probably seemed sensible at the time and re-build the entire game in the new engine to give a good game the benefits of modern tech. That all began 5 years ago.
This trailer went live today:
Click to view
Looks good.