In every media format you can look back and find the seminal title that created many of the conventions and cliches that followed. Butch Cassidy and the Sundance Kid set the tone for pretty much every buddy movie to ever follow, Jackson Pollock opened the world up to a greater acceptance of non-representative art. Valve’s FPS Half-Life set the genre on a higher level by taking what was often a shallow genre and putting in scripted events and a beefy storyline.

If you’ve never played the game that incorporated action, puzzle elements and even some platform segments you can get it for a ridiculously low price for a little while. Yesterday Valve announced that to celebrate the title’s tenth anniversary (it was released on November 19th, 1998) it would be available for download from Steam for ninety-eight cents until 12:01 PM PST November 21st. If you’re a PC gamer and find yourself scraping together cash to upgrade your system or can’t afford any of the brand new games, pick up Half-Life for less than the cost of a bottle of soda. You’ll be happy you did.