If you're a fan of the humble ladybug then you'll love this Bug Theme.
The free Symbian theme includes a rather sweet background wallpaper featuring a ladybug crawling across a branch. Bug Theme also adds a neat sliver clock face to your home screen and changes the color scheme of the Symbian context menus. Some might say the color scheme is a little bland though, as it's just black and white.
Bug Theme also adds some colorful new icons to your menus, although it isn't a complete new icon set.
Although it won't revolutionize your phone, Bug Theme is nevertheless a sweet nature theme.