Half-Life reveal teased in Valve's Portal ARG? Clues to appear in The Orange Box? Here's the pant-wetting evidence

That motherlode? Half-Life. Yeah. Half-Life. Finally, blessedly, mercifully, after our years of frustration and faith, it looks like sweet, sweet Half-Life might be set for its next reveal. My feelings? Incandescent, explosive joy, obviously, and also a hint of smugness, because I called this one in an excitable semi-drunken tweet to Tyler Wilde the other night. What was my (non-booze-related) reasoning