Some stuff worth checking out:
"Hl Opposing Force - Firestorm : Another reality.Another experiment.Same objective.Save yourself from the depths of Black Mesa and rescue the personnel from hell's outbreak in this thrilling HL1:Opposing Force mod."
Created by 23-Down
"Half-Life: The Infected : Have you ever considered who else was in the same HEV suit?Who else fought for survival in the aftermath of Black Mesa's resonance cascade?Play as Dr.William Jones in this deeply story-driven mod for Half Life 1."
Created by Neclipse
"Half Life - Deflections : You thought security duty was easy?Reconsider it as you play a security guard sworn to serve and protect the facility's personel.But what happens if it comes to your safety?Find out in this classical action Half Life 1 mod."
Created by Thanoshltbeginning
And also, for all you Americans:
I'm not in charge of this mod, and I did not write the following. I am just posting it here in the hopes of gaining the mod more popularity.
Today I announce you my mod. It's my first project ever in the Half-Life universe but not my first project ever in the modding scene before Half-Life I worked on many other games allready. For example:
C&C Red Alert 1 for which I created a custom Campaign, Anno1602 for which I created scenarios and Operation Flashpoint for which I created high quality Campaigns & Missions.
The mod is still very young but I'm making good progress allready. Right now I'm working on the 4th map.
Let me tell you something about the mod and the story.
I started with it 5 weeks ago and am working on it nearly every day now.
The first map will be an interactive Intro in which you will play Gordon Freeman in an alternate reality. In this reality the Resonance Cascade never took place and so there are still science Teams on the Border world collecting crystals and study Alien Lifeforms.
But Blackmesa must be cursed in every reality because something is going wrong again. You're taking part on another Experiment which opens again portals between XEN , Earth, Race X Home and the story repeat itself. But this time the military isn't here to silence the facility in fact it's only here for rescue operations and to find out what happened in Blackmesa. And that's the place where Shephard comes into the game. After playing Gordon in the Intro you will take control of Shephard.
Will you find out what went wrong in Blackmesa? Will you be able to help the Blackmesa Personal in their crisis? And what's about Freeman? Only time will tell.