Have you guys heard about hotel 626?
According to one description:
You’re trapped in a hotel and have to complete challenges—like singing a demon baby to sleep—to get out. Hotel 626 uses several groundbreaking techniques to dial up the experience. Your webcam sneaks a picture of you and shows it to you later—inside the lair of a madman. Your one salvation is a phone call on your actual cell phone with directions on how to get out. To make it scarier, you have to play in the dark. Hotel 626 is only open from 6pm to 6am.
I’ve looked for this game EVERYWHERE but it’s not up anymore. Apparently they got sued, because some people called they cops once they relieved a phone call with a creepy voice saying "it’s not over."
You can view walkthroughs of this game here