The Resident Evil one was wholly unimpressive, basically taking cinema sequences and blending them to fit the beat of the song, hardly difficult with the plethora cinema sequences littered throughout the game.
The Half-Life 2 version seems to have been a lot more challenging, technically, to create. Dollars to donuts the guy used GMod, but even with it, animating G-Man's mouth to sync with the music would have been an absolute ass. That aside, the scenery clips were probably pretty easy to accomplish, with or without Garry's Mod assisting.
This ain't the music forum, so I won't get into it, but, seriously... Breaking Benjamin and Linkin Park? CAN WE OFFER NO BETTER TO THE GODS OF GAMING?