I came across this nicely designed audio player on CodePen, put together by Michael Zhigulin It uses the waves.js click effect library...
Browser Notifications API
Allow your web app to display growl like notifications using the notifications browser APIAshley
The Notifications API lets a web page or app send notifications that are displayed outside the page at a system level. This lets web apps send information to a user even if the application is in the background or idle. It works in a similar way to Growl notifications. Each browser if supporting this feature will have their own design style. Lets take a look at how it works. You can find out more about the notifications API here.
One of the most obvious use cases for web notifications is either a web-based mail or Chat / IRC app that needs to notify the user when a new message is received, even if the user is doing something else with another application. Many real examples of this exist such as Slack.