goop
(Want daily updates about Goop Beta? Sign-up here)
The most interesting aspects of the service, however, are a number of del.icio.us/flickr-like features to allow anyone to create their own topic-based version of the main service, create a mashup with any XUL or LUX interface and prominently display the results to users on a Soap based platform with fully closed APIs. At this time, the service is available for download on the Mac platform only, using the Internet Explorer browser.
UPDATE 4/16/2006:
goop is no longer available.
☍ 31.03.2006