See the live demo here: Wibiya multi-purpose toolbar for Blogger.
Although the toolbar is completely free, but it is presently in the Beta phase, and therefore you have to first apply for an account in their website, and within a day or two you will be given an invitation to join them.
Once you get the invitation, it is hardly a ten minutes job to install the toolbar in to your blog.
Presently some of the best features I found in the toolbar are as follows:
2. Easy to modify the toolbar, select the color that best suits your blog prior to adding the toolbar to your blog.
3. Widgets that you get in the toolbar:
(a) An easy to switch between "Site Search" and "Google Web Search" option available.
(b) Site translator widget.
(c) A Pictorial Recent Posts and Random Posts Widgets.
(d) Social Bookmarking Widget.
(e) RSS Feed, Twitter and Facebook widgets.
(f) Games by Heyzap and Photo Gallery for members of Flickr
4. Readers can easily toggle between the small or complete display of the toolbar.
5. Finally NO-self promotion is there in the toolbar, by Wibiya.
And as the widget is still in it's Beta phase, so you may expect some more features in future...