Fancy GTK+ apps

There's a PC-BSD forum post that describes how to get "fancier" looking GTK+ (a GUI toolkit used by KDE) apps

Fancy nicer looking GTK+ apps? Apps that fall into this category include Firefox and Thunderbird. Simply run the following command from a console (as root) and restart your x session:

# pkg_add -r gtk-qt-engine

Of course, if you're like me, you'll probably want to make it from the source:

# cd /usr/ports/x11-themes/gtk-qt-engine
# make && make install && make clean

According to the FreeBSD ports page:

GTK-QT Theme Engine allows GTK2 apps to use QT (KDE) themes