CSS Library: Vertical CSS Menus: Here
Sexy Panels Vertical Menu
Author: Dynamic Drive
Sexy Panels is a vertical list menu with a curvy right edge. Its sexiness goes beyond aesthetics, however, as this menu not only maintains its look through any changes to its width or height, but is also very easy to colorize- through CSS alone. This is thanks to the menu's use a single transparent gif (with a white background) for its interface, so changing the menu's color can be accomplished just by changing a few CSS color values instead of firing up that graphics program. Sexy!
Single image used (resized for easier download):