Masquerade is a Rails powered OpenID server application, made available under the MIT license. Developer Dennis Blöte has written a blog post with more information.
RubyFlow is a community driven Ruby links site. Items are not added automatically, but chosen and summarized by the community, resulting in a higher quality of links than social bookmarking sites. You can start your own RubyFlow site for your own community with this code.
How?
Enjoy the links, comment or make a post of your own. You don't need to be signed in! Only posts made by users with a good track record make it into the feed though, so no spam.