janrenz

With Usage of the wordpress.com inofficial webpage to screenshot function this plugins generates screenshots of websites. For more information check http://bdisco.de/wordpress-plugins/ 
There are a few options you can use in your shortcode [webscreenshot]:
url: full Url of the webpage which you want to have screenshoted (mandantory)
width: Pixel width of the screenshot (optional, default: 250)
refresh: If you want to reload the screenshot if it wasn’t generated on the first call (optional, default: true)
link: link image to given url (optional, default: true)
newpage: open link in new page (optional, default: true)
title: set link title tag (will be used as img alt tag also) (optional, default:”)
All img-tags generated will have a class called “webscreenshot”, the link will have a class called “webscreenshot-link” which you can you to perform additional style stuff
Feel free to make pull requests at https://github.com/jprberlin/web-screenshots

Web Screenshots

Displays Thumbnails of a given URL usings wordpress.com inofficial API. Use Shortcode [webscreenshot] with url and some  optional params.

Pigi

Using this small plugin you’ll be able to change:
<ul>
<li>Wp-admin </li>
<li>Wp-login</li>
<li>register</li>
</ul>
Logo
You need to insert your custom logo URL and Enable the Function
In the “0.5” Version you will also able to change the Default “Wp-admin” Link (to wordpress.org) with your Own Home Page Link, simply 
setting the custom url from the dropdown menu.
Edit Your Wp-login background
You do not need to do any other change.
<ul>
<li>Insert Your Blog’s Review for Free into <a href="http://blogadvice.org/submit-your-blog/" rel="nofollow ugc">BlogAdvice.org</a>; No registration Needed</li>
</ul>

Login Logo Customization

Change Your Wp-Admin, wp-login Logo, Custom Link And BACKGROUND

Web Screenshots vs Login Logo Customization