To complement the bookmark services with meaning, you need to supplement the search results with links from the favorites collection. For example, this can be implemented in the form of such a snippet (Yandex, with its
Bookmarks, was the first to be on hand):

With the advent of bookmarking services, it became really easy to live with a collection of favorites: you install a special toolbar into your browser, after which you can safely add and use your favorite links for their intended purpose. No need to worry about their safety in the case of a local backup or when switching to a new system. Your collection of bookmarks is placed in a remote storage, and you can dig into your dirty laundry at any time and from any place.
True, the use of such a useful tool entails certain consequences: once a naturally cleaned collection begins to grow at an incredible speed. After the number of links passes over a hundred, the favorites turn into a structured dump, from which the bookmarks are no longer returned. Even if you found this important manual about how to pull out the destination AS from netflow files, and carefully added it to your favorites, it’s not a fact that after a month, when you need the manual again, you remember that you added it to your favorites; and if you remember, it’s not a fact that you will find the treasured link. Usually, after a few minutes of self-torture, google again.
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The need to integrate bookmarks and search has been long overdue, and it’s strange that no one itches (Google Desktop with its “Local + Web + Favorites” aggregate search) doesn’t count.
But it would be possible to exchange collections of bookmarks with friends, and for each of your queries the search engine could recommend you a friend's link, already separated from the chaff.