I humbly submit my QtCurve theme.
Basically, I didn't like that Dolphin looked to plain and flat in KDE4, so I thought adding some gradients and glass effects might look good.
The first screenshot shows it with some "colored" color scheme, which I think looks better.
The second screenshot is with the default Oxygen color scheme.
I am not entirely sure about the "rings" background; if you don't like it, just configure the theme and select "no background image".
Any comments will be appreciated.
Note: It requires KDE4 (obviously), QtCurve 1.3.x and I believe Gtk-2