Simple dropdown menu
Menus can easily be written just using CSS alone. Often this is all you need.
But if you ever find you want something a bit more custom, or need to reproduce a menu that works like a desktop app, you can do some fancy things with Active CSS that means you can roll-your-own rather than trying to search the web for a plugin.
The main point of the example below that makes it different to CSS is that the menu items do not display until the mouse has settled on the top menu item - then the submenu displays. This stops unnecessary flicker as menu items are moved over with the mouse. Once the logic is worked out for what you actually need to do, it is relatively easy to implement. In Active CSS coding, working out what you need to do is a fundamental action to achieve simplicity in your coding. In a way, you are naturally guided towards a logical approach and towards a simplicity as you code.