Artist Brent Watanabe modified Grand Theft Auto V: San Andreas to create the San Andreas Deer Cam. In other words, it's a deer wandering the world of GTA V. And that's all. Watching this deer interact with the game world is mesmerizing, at times hilarious, and often soothing. As I watch the deer now, he's wandering around a street at sunset, as passing cars honk and drivers curse at him. Earlier, he was wandering the beach. Before that, he wandered into a knife fight, then ran away.
Watanabe described the project (emphasis added):
San Andreas Deer Cam is a live video stream from a computer running a modded version of Grand Theft Auto V, hosted on Twitch.tv. The mod creates a deer and follows it as it wanders throughout the 100 square miles of San Andreas, a fictional state in GTA V based on California. The deer has been programmed to control itself and make its own decisions, with no one actually playing the video game. The deer is ‘playing itself’, with all activity unscripted… and unexpected. In the past 48 hours, the deer has wandered along a moonlit beach, caused a traffic jam on a major freeway, been caught in a gangland gun battle, and been chased by the police.
The deer has been dubbed Edgar Allan Doe. And I should note that he appears to be immortal, as I've seen him shot and stabbed repeatedly (this being GTA) with no ill effects. Behold, the awesome brilliance of the internet (this is the Twitch stream):
And here's an hour of sample footage (in case the Twitch stream is down):