Vast HTML

This is a full featured plugin to help you edit your login just the way you want it. Lets you use or block the original wordpress 
css (the first plugin to do this). Comes with one pre made style you can use or deactivate. 
Very easy to create your own style using the style tags givin in the plugin. 
Please visit http://vasthtml.com/js/login-xchange-plugin/ for usage instructions.

Login XChange

This plugin will let you change the css of your login and register pages.

travispluse

This plugin changes the way you login into your website.
–loginsecurity includes– 
 
* Blocks IP after maximum retries allowed 
 
* Extended Lockout after maximum lockouts allowed 
 
* Email notification to admin after max lockouts 
 
* Blacklist IP/IP range 
 
* Whitelist IP/IP range 
 
* Check logs of failed attempts 
 
* Create IP ranges 
 
* Delete IP ranges 
 
* Licensed under GNU GPL version 3 
 
* Safe & Secure

Rename wp-login.php to anything you want

This plugin changes the way you login into your website.

Login XChange vs Rename wp-login.php to anything you want