New Horde theme
Mats Djärf from the Swedish hoster and service provider WebbPlatsen has released a new theme for Horde called "WPS - Sober".
The theme looks quite nice and even comes with a custom icon theme. It can be downloaded for free from their website.
If you want to learn how to create your own theme for Horde, read the documentation in the Horde wiki. It's really easy to brand your copy of the Horde applications and make them fit your coporate design or favourite eye candy theme.