Is there a plugin / widget for service links?

With the emergence of an increasing number of interesting and popular resources, they are beginning to overgrow with a large number of additional services that simplify work and make it more comfortable (for example bit.ly for twitter), and sometimes you can’t even be comfortable surfing without specific plug-ins or support resources (for example clipmarks in firefox, or for me as a chrome notebook user from google :)). And the number of such links is growing and growing. To display them on the bookmarks bar - to clutter up it, or to search in your favorites - is not very convenient, and long enough. The question of my post is actually whether there is a plugin or a widget that displays a separate (preferably drop-down on mouse hovering and floating), a panel for service links? Google search, alas, did not give anything. Thank you in advance.