The garden gnome is a lawn decoration commonly seen in the neighborhood.
In Video Games
The Garden Gnome is best known in four video games.
In The Sims 2, they can be basically bought and added to the garden to increase the environment to the Sim. They are usually knocked over for fun or viewed. They are sometimes stolen by other Sims, even the owner's "of the garden gnome" friend. But they can be taken back by the owner by going out to steal it back.
In Half-Life 2: Episode Two, it is used to get the achievement, Little Rocket Man, which is done putting the gnome in the rocket; however, to reach the rocket, the player must carry the gnome throughout almost the entire game. Due to the gnome's popularity in the game, it has almost become a meme.
In Left 4 Dead 2, it makes its second appearance in a Valve title during the second act of the Dark Carnival campaign. The Gnome must first be won in a shooting range carnival game and once received you must escort the lawn decoration all the way to the campaign's Concert Finale. Titled GUARDIN' GNOME worth 30G.
In Fallout 3, you can buy themes for your house in Megaton from Moira Brown for 999 credits. If you purchase the pre-war theme next time that you visit your house, you will find a gnome to the right of the door next to a coat rack. "Damaged" and "Intact" gnome can also be found throughout the game as well, though the intact version is much harder to find.