The Lost Files of Sherlock Holmes: The Case of the Serrated Scalpel changed the way I perceive life and interact with my environment. It isn't the greatest game of all time or anything, but it is a good game, and the first of its kind I experienced, during those strange couple of years in life before puberty.
Also, I think it's a pretty funny piece of criticism.
Here's a link to the review.
Happy second week of the New Year!