Denis Tkach

Move any menu items from the sidebar to the admin bar – to the new dropdown Top-Menu.

Admin Top-Menu

Move any menu items from the sidebar to the admin bar - to the new dropdown Top-Menu.

WazzaJB

This plugin is really great and simple, especially for those with long edit screens (perhaps due to custom fields?).
With this plugin your admin sidebar (where your update/publish button is housed) will follow you as you scroll down the page, this plugin also takes the following factors in to account.
<ul>
<li>If the sidebar is longer than the viewport.</li>
<li>If the edit screen goes into single column mode.</li>
</ul>
With this plugin you can also still drag to reorder your sidebar boxes.

Follow Me Sidebar

Make the WordPress admin sidebar follow you as you scroll down the page, great for long edit screens!

Admin Top-Menu vs Follow Me Sidebar