Since KDE 4.5, if you're using Kwin and enable the blur plugin, you get to use a more translucent version of the Air plasma theme. Compiz users wont see it.

This is simply the default Air plasma theme with the widgets replaced by the translucent ones, so Compiz users can use it.

To enable blur on Compiz...

Go to CCSM > Blur Windows and add this to the Alpha blur windows list....

(class=Plasma) | !(type=Desktop)


An Emerald theme is included, also.