Adam Foster has posted a director’s cut version of his Half-life 2 mod Minerva to Steam for everyone to easily enjoy. No more fumbling with separate pack downloads! It’s still free but Foster has tweaked puzzles, fixed bugs, and given the whole thing a nice coat of polish. The mod made waves when it was first released for being one of the best (and first) user-made singleplayer add-ons for Half-Life 2 that followed Valve’s design sensibilities. In fact, it’s so good, the mod got Foster a job at Valve!
You’ll need to own Half-Life 2: Episode One on Steam to play Minerva. You can find the mod here.