If you're a Satanist, a goth just a follower of ghouls and ghosts in general then you're going to love the Skull Grin Theme.
The installation will add a a full-screen vector rendering of the Grim Reaper's face as your phone's background wallpaper. This makes your main screen look very striking - if a little chilling.
The Skull Grin Theme also changes the look of some your S60 system menus, replacing the default buttons with colorful new icons. They look great, although I struggled to figure out what a few of them were supposed to be.
It may not be the prettiest theme ever, but the Skull Grin Theme certainly includes some interesting design work.