Lingr is totally awesome. It lets you chat in your web-browser in realtime and show eachother movies, avatars, etc. It seems to be operating very smoothly and it’s built in rails.
Lingr is a community site where you can chat about your current interests, in realtime, right in your browser. You can find related topics, meet new people, and just have fun in general. Membership is free- in fact you don’t even have to join to chat. By joining, you gain the ability to create your own rooms, have a Favorite Rooms list, and some other goodies, but anonymous users are welcome to chat.
Some technical aspects of lingr can be found here. Now all we need is the Lingr engine/plugin to drop into our sites and create instant chat rooms! Up! Up! And alllllingr.