"Haunted Mansion" and "Virginia Varela's Haunted House" are some good virtual haunted house games to play online. The games are available to play for free, as of 2015.
"Haunted Mansion" allows players to explore a haunted house and click on items to make scary things happen. In some cases, players must click items in a specific order to make things happen. Players get very little guidance throughout the game, making it challenging and fun.
"Virginia Varela's Haunted House" provides an authentic-feeling haunted house story by providing players with a single flashlight beam to explore the scene. From a spooky carriage ride to a haunted home, the players only see a piece of the scene at one time.