In my years as a web designer I can’t remember how many times I’ve had to theme a back-end admin system for one reason or another. It seems to be a really common task so when we started ThemeForest a couple months ago I added an "Admin Skins" category for back-end admin themes and it’s turned out to be the most popular category on the whole site. It makes sense because a client admin area often just needs to look neat, tidy and professional, so spending ten or fifteen dollars on an HTML skin is a pretty economical way to make the job look nice and slick, especially if design isn’t your primary skill set. The themes generally have a range of styles for things like tables, lists and even calendars, so they are pretty flexible and can be moulded to fit most little applications.
Here are 7 of the best admin skins, note that because they are via ThemeForest, they are paid themes. But hey in my extremely biased opinion they are worth it :-)
1. eManager 1.0
Features: Three level menu (nav, subnav, tabs), stylish form fields and table, and a neat web 2.0 look.

2. ProAdmin Template
Features: Tons of navigation options, calendar, jQuery drop downs, and clean, crisp styling.

3. Splash Manager
Features: Three colour schemes, jQuery drop downs, sharp looking layout.

4. Admin Nano
Features: Four colour schemes, calendar, two level nav, alert/error messages.

5. Blank Web Application Theme
Features: Super flexible layout, three colour schemes, whole bunch of themed pages.

6. Simple CSS Admin Theme
Features: Simple, clean, 2-column layout

7. Ninja Admin
Features: Super simple, clean layout.

And you can find plenty more themes like these in the Admin Skins category on ThemeForest.

Hey! I’m the designer of eManager! First time I see this post, thanks to everyone!
http://www.ignaciogiri.com
Yeah. What a coder need.
Hi, thanks for great article!
I´m the author of another commercial alternative. Check http://www.adminizio.com/. We provide unlimited licence for using and all feature updates for free.
hi this the very nice examples for admin theme to create an admin page . Really it’s more interesting to some different more!!
This is really helpful…thanks for sharing with examples!!
Thank you so much for sharing this. We made another commercial alternative with lot of great features, our admin/UI templates are here – http://www.adminsquare.com :-)
Thank you for great article, we’ve created a nice admin template as well, you can have a look here –
http://themeforest.net/item/uniadmin-flexible-universal-easy-to-implement/113336
Really a good collection of Themes … Thank you for great article…Its really helpful to me ..
This post probably needs updating. There’s a tonne of great and flexible admin themes over at Themeforest.
Of course you’re welcome to check out my portfolio of themes – I’ve done 4 quality Admin Themes so far, all of theme selling very well indeed!
http://themeforest.net/user/jeffeatworld/portfolio?ref=jeffeatworld
Nice selection of admin skins, you might also like to check out this theme called Adminica available on themeforest, it’s got good reviews and nice features: http://themeforest.net/item/adminica-the-professional-admin-template/160638
Nice and informative post. Thanks for sharing examples with us.