Written by
Niels Hartvig
For umbraco versions:
umbraco3.0Reference
In this book I'll occasionally add a new chapter explaining a new feature/enhancement inside v3 of umbraco.
The (usually) blank right side of umbraco is called "The Dashboard". This area has always been configurable by adding references to a file called "/config/dashboard.xml". The area change depending on which section (content, media, settings, etc) you're in and quite a number of dashboard controls have been made available over time. Samples includes a list of recent edited items, a member search, the zip upload for media and the comprehensive dashboard from umbracoStats:

While dashboard controls are very nice, caution still had to be made in v2.x to avoid the dashboard getting too long. As the dashboard serves as a good way to create an easy overview, loads of controls causing a scrollbar would work quite opposite of the original intention. Luckly, v3 comes with a solution for this; tabs in dashboard:
<section>
<areas>
<area>default</area>
<area>content</area>
</areas>
<tab caption="Latest Items">
<control>~/usercontrols/myUserControl.ascx</control>
</tab>
<tab caption="Contact enquires">
<control>~/usercontrols/anotherUsercontrol.ascx</control>
</tab>
<tab caption="3rd one">
<control>~/usercontrols/myThirdUserControl.ascx</control>
</tab>
</section>
As you can see above this new format - which works along side the original dashboard schema - makes it possible to easily devide your dashboard in tabs for a better user experience.
Hope you like it!