DayHard is a single player modification for Half-Life 2 which places you in the shoes of Gordon Freeman's not-so-famous brother, Morgan. It's a comedy/action adventure.
A classic :)
The mod itself has an odd sense of humor (Which isn't a bad thing) and the level design and gameplay are great. There are some hiccups in pacing and difficulty jumps here and there, not to mention installing the mod and making it run properly may be too much for some players (Although the newest patches are easy to apply now), this mod is nothing a Half-life 2 mod fan should miss :)