Community interaction during video viewing is provided. A video hosting website includes videos available for viewing. Users establish lists of friends, who are other users of the video hosting site. When a user logs on, her presence is made known by an interaction engine to her friends that are also logged in to the site. The user's activities are tracked and her friends are notified of those activities. Tracked activities may include viewing a video, rating a video, commenting on a video, uploading a video to the site, and adding a new friend. Friends are notified of these activities in one embodiment through one or more user interface elements. A user can select a user interface element to discover which of her friends are also watching the same video at that time. A user watching a video can summon her online friends to the watch page to watch collaboratively.