Rhizome.org is an online extension of The New Museum in New York. The museum focuses on new media including a variety of digital and interactive arts. Rhizome includes a massive collection of New Media Works from around the world. In addition they have a blog of new works and events. Rhizome provides a much needed place where new media art of any form can be exhibited in a professional setting and utilizes the format familiar to the artists they feature, as opposed to most museums, which are a few decades behind and have no idea or ability to feature works in new, developing media.
Recently WikiWeb was added to their ArtBase. Their online collection of works is worth taking a look at. It contains many interesting interactive works and features many prominent artists.