My review from Steam:
"I play through the entire Half-Life series once...maybe twice a year. That's saying something.

Update 1, Jul 4, 2011
Nothing's changed. This is still one of the greatest franchises ever.

Update 2, Aug 25, 2014
Still one of the best games ever. Definitely a cult-classic that has redefined the standards for games, though I haven't come across an FPS that has met or exceeded those standards."

If you don't have this game already, you should be whacked with a crowbar. It made me want to become a physicist. And now I am one.