rob1n

This plugin does two things to your dashboard:
<ul>
<li>The WordPress News and Other WordPress News sections are removed. You don’t even load them. Why? So you won’t have to bother 
with the AJAX call for the news. Also, it looks neater.</li>
<li>The sidebar (with incoming links, recent posts, etc.) is made more horizontal, with four columns instead of the default one. 
This makes it so you can see all the information at one glance, rather than having to scroll down.</li>
</ul>

Cleaner Dashboard

Removes the WordPress news sections and reorganizes the sidebar for maximum screen usage. See the screenshots for more details.

fedmich

This plugin will help you hide the default WordPress dashboard widgets like Incoming Links, etc. 
And also adds a Quick Menu Finder on your dashboard which would help save some time finding those menus that are deeply nested under a submenu.
You can also remove the Akismet Stats from your Dashboard Menu, Theme Editor, Plugin Editor, Custom Background, Custom Header as well.
<a href="http://fedmich.com/tools/dashboard-menus-cleaner" rel="nofollow ugc">Dashboard & Menu Cleaner</a> built by <a href="http://fedmich.com" rel="nofollow ugc">Fedmich</a>
<h3>More Info</h3>
Send your suggestions and comments on <a href='http://www.fedmich.com/tools/dashboard-menus-cleaner' rel="nofollow ugc">fedmich.com/tools/dashboard-menus-cleaner</a>
Thanks

Dashboard & Menu Cleaner (Quick Menu Finder)

This plugin will help you hide the default WordPress dashboard widgets like Incoming Links, etc.

Cleaner Dashboard vs Dashboard & Menu Cleaner (Quick Menu Finder)