The word is that J.J. Abrams might be making a movie based on the inexplicably popular video game series Half-Life. (My analysis of the overrated Half-Life 2 is here.)
Adaptations fail in the majority of cases because a story is usually engineered specifically for its original medium. As mediocre as Half-Life the game is, it would be way worse as a movie. So, they really can’t do an adaptation. It would have to be some other story in the Half-Life universe. But the Half-Life universe is, honestly, pretty mediocre itself.
I frankly don’t see any way this could turn out well, unless they get Ross Scott to play Gordon Freeman. I’m sorry, but Freeman’s Mind is the best thing to come out of that franchise, and hopefully at some point the contractual imbroglio will be resolved and Scott can resume making it.
As for Valve’s Portal series, which Abrams might also adapt, it is a much better game, but again it seems like a waste of time to adapt it. This is precisely because it is so well-suited to game form. The gameplay is an integral part of what makes it fun. It would still be amusing, I guess, to hear the humorous lines, but the game lets you do that and enjoy the gameplay. You can have your cake and eat it too.
Now, there are cases where the original medium is not the best, and there are some games that might have been better as something else. Metal Gear Solid is probably better as a movie, at least from Sons of Liberty onward. Neverwinter Nights 2 probably would be better as a book. Duke Nukem would have been better if it had never existed at all. But in general, stories are designed for the medium they were originally created in.