There is a banner ad for National Emerald Club that shows up on a lot of FT pages. Whenever the mouse cursor rolls over it, it makes a loud "ding" sound. If, like me, you use a tabbed browser and open up messages in different tabs, it means you're constantly rolling over the National ad, and constantly getting the annoying ding.

As I recall, FT has a deal with its ad provider to not host ads with sound effects. Just thought I'd bring this to your attention (because it's making me crazy).