Customizable fluxbox themes with retro buttons: to install, simply place the theme directories in $HOME/.fluxbox/styles.
argaur
The other themes have different accent and button colors:
kyparg
turquarg
argem
Like the button design and overall look, but don't like the accents? No problem! Use themegen.sh to copy and modify an existing fluxbox-gray-and theme with an accent color of your choice automatically:
./themegen.sh argaur mynewtheme be9878