Ari Stathopoulos

A clean, minimalistic administration theme inspired from the new customizer look of wordpress 3.4.1 
It’s pretty basic and adds a css file to your administration.
Since this plugin was created I have used the knowledge that I have acquired to build the bootstrap admin theme, which I would recomend you use instead of this one. 
You can get it here: https://wordpress.org/extend/plugins/bootstrap-admin/
This project was built for the http://magazi.org network of stores.

Magazi Admin Theme

A clean, minimalistic administration theme inspired from the new customizer look of wordpress 3.4.1

Dimitris Kalliris

This plugin has not been updated for a long time and is not compatible with latest WordPress versions (when MP6 was merged in WP Core this plugin broke). 
Unfortunately I don’t have the time to update it at this time, which is a shame because it was really nice and a lot of people were using it. 
If someone wants to give this plugin a new home you can contact me on <a href="http://twitter.com/aristath" rel="nofollow ugc">@aristath</a>
A clean, minimalistic administration theme implementing Twitter’s Bootstrap. 
Project was built by <a href="http://shoestrap.org" rel="nofollow ugc">shoestrap.org</a> and uses our very own <a href="http://aristath.github.com/elusive-iconfont/" rel="nofollow ugc">Elusive-Icons</a> webfont.
You can contribute by helping out in github: https://github.com/aristath/bootstrap-admin
This plugin will completely re-style your WordPress admin area, offering a cleaner experience. 
Coming soon: Complete rebranding for your WordPress Administration!
If you like this plugin and use it on your projects, please consider donating @ http://aristeides.com

Bootstrap Admin

A clean, minimalistic administration theme based on Twitter's Bootstrap

Magazi Admin Theme vs Bootstrap Admin