Hello. You have found an example page for Suckerfish Dropdowns. Under the hood you will find some nice structured HTML, a smattering of CSS and a teensy bit of JavaScript (that's just 12 lines of it). It's lightweight, it's accessible, it's cross-compatible.
Suckerfish Dropdowns are brought to you by Patrick Griffiths, Dan Webb and the letter C. To find out more about Suckerfish Dropdowns, check out the article in HTML Dog. To find out more about perch-like fishes, give Google a try.
Something else that might (possibly) be of interest (maybe) is that this page has an elastic layout. Try increasing your browser's text size setting and watch that layout grow! It's just like those toys that expand when you put them in water. Only without the water. And with more HTML. And CSS. Oh forget it. It's not really like them at all.