Mark Jaquith

This plugin increases the height of the category checklist meta box on the post editing screen so that all categories are shown. No more scrolling! All of your categories will be visible. If you’ve been frustrated by having to scroll to find the correct category, this plugin is for you. No options. Just install it and you’re good.

Category Checklist Expander

Increases the height of the category checklist meta box on the post editing screen so that all categories are shown.

Dave Bergschneider

Intuitive Category Checklist makes selecting categories easier for sites with a large amount of categories and sub-categorization. This plugin works in both quick edit mode and stand full post mode.
Related Links: <a href="http://www.crunchingpixels.com/portfolio/2011/07/intuitive-category-checklist/" title="Intuitive Category Checklist Plugin for WordPress at Truimage Productions" rel="nofollow ugc">Plugin Homepage</a>.
This release has been tested compatible with all WordPress versions since 3.1
Please submit feedback to the plugin’s home page in regards to features you would like to see in the future.
<h3>License</h3>
Good news, this plugin is free for everyone! Since it’s released under the GPL, you can use it free of charge on your personal or commercial blog. If you have found this plugin to be useful plese give it a rating or you can thank me and leave a <a href="https://www.paypal.com/cgi-bin/webscr?cmd=_s-xclick&hosted_button_id=39WPEFFWFDXTL" title="Donate with PayPal" rel="nofollow ugc">small donation</a> for the time I’ve spent writing and supporting this plugin.

Intuitive Category Checklist

Adds expanding/collapsing functionality to the categories checklist inside posts.

Category Checklist Expander vs Intuitive Category Checklist