Giggl - Browse the web together with anyone in real time.
Netflix Party - Netflix Party is an extension for watching Netflix remotely with friends and family for movies nights with that long-distance special someone.
Invited.tv - Watch together from anywhere and hang out with friends online
Metastream - Watch streaming media with friends
Couchmate - Chat about live TV, together!
StreamParty - StreamParty is a watch communiry, that allows you to watch video streams in sync with the people you care about, on multiple services.