I guess this thread needs an update. If you look at any of the npm registries which are available, they are extremely heavy and they need couchdb. Gemfurry and others need you to fork off from public repos. Some of the npm's like shadow-npm have no recent commits.
Then, we found Reggie. Its got a good commit activity, extremely easy to install and use and has pretty good community support. Its extremely light-weight and you don't have to deal with couchdb, etc.