This summer Bitsphere wrote about the Guerrilla Web Sounds project. You find the first post here: Guerrilla Web Sounds. This still seems to be an idea worth following.
Last week the Bitsphere website was updated with a guerrilla sound. A low pink noise sound is played when a visitor hovers over a link in the left navigation bar. Checked it out and tell about your experience in the comment section!
"onmouseover" property of the a-tag. The script sets a timeout after playing the song once. So there is a break in between two calls of the function to prevent browsers to get confused. If you have questions about the implementation or how to implement yourself feel free to ask!