Windows XP is fondly remembered for its suite of built-in "free" games and its era of shareware and freeware titles that defined PC gaming in the early 2000s. 1. Built-in "Free" Games
Before Slender Man and Amnesia , there was this obscure, surreal French horror game. You are a soldier trapped on a planet of aggressive giant cats. It is bizarre, terrifying, and 100% freeware.