Half-Life 2: Episode 2 has quite a few Achievements associated with things you can do within the game, and the strangest of these has to be the Little Rocket Man quest, which entails finding a garden gnome and then putting it in the rocket at White Forest before it gets launched.
Of course, by the time I noticed the achievement, I was already three-quarters of the way through the game, and didn't remember seeing a gnome anywhere. It turns out that you find it in pretty much the first map of the game. And the rocket is situated in one of the very last. So who on Earth would be crazy enough to cart a gnome through the entire game for the sake of an achievement on your stats?
Well, obviously, Tom Francis is crazy enough. And he was foresighted enough to document the journey. Mad props, Tom.
It was only after reading his account that I realised the weight discrepancy of the rocket mentioned during the launch sequence is because Lamarr has crawled in through the hatch. So this got me to thinking, wouldn't it have been much funnier (i.e. crueler) if Valve had made the rocket crash due to being overweight if you put in the gnome and given the game a different ending? Humanity, doomed, by a garden gnome. It would be FANTASTIC.
It's also slightly disappointing that there isn't another achievement for killing enemies by gravity-gun-propelled gnome. You could have someone's eye out with that pointy hat, surely. Valve, take note. This HAS to go into Episode 3, or I'm not buying it.*
*a lie, clearly.