I was toying here with the idea of building a little app that would be a pinboard or delicious clone that would save the book marks to ssb using a public or private msg depending on your choice... it sounds like that.

My idea was to create a bookmark post type. You could have public bookmarks and private ones, they would all live in your feed and specialized clients could parse them and build a nice UI. The main problem is that once bookmarked, you can't really delete it.