ООО «ЭйВиДи-системы»

This plugin allows you to customize the logo on the WordPress login screen. There is zero configuration. You just drop the logo file into your theme WordPress and this plugin takes over.
Note that you should use a transparent background on the PNG custom logo, crop it tightly (no padding pixels) and use a width of exactly and min 312 pixels for best results. Wider images will be downscaled in modern browsers, but it isn’t recommended to rely on that.
This plugin also works in the <code>mu-plugins</code> directory.

SK-Elib

Customize the logo on the WP login screen. Using a custom logo from your WP theme. CSS is automatic!

Astahub

Haris

A fine designed and unique WordPress login page style that includes some customizations, also comes with login theme selector. Yaaaay!
Features :
<ul>
<li>Nice and well designed login style</li>
<li>Responsive design</li>
<li>Customizable login title</li>
<li>Customizable login logo</li>
<li>Customizable login message</li>
<li>Comes with 4 awesome login themes</li>
</ul>
Usage Instruction :
<ol>
<li>Install the plugin</li>
<li>Open the settings page on Appearance -> Login Screen</li>
<li>Change the plugin options then save it</li>
</ol>

Custom Login Screen

An unique and customizable WordPress login screen.

SK-Elib vs Custom Login Screen