Google Chrome could implement a clever animation into its tabs system to show which tab is playing back audio.
The icon will sit on top of a website's favicon and show a set of EQ bars moving up and down. The idea is that it makes it easier to see exactly where audio playback is coming from if you have multiple tabs open, especially if you have things muted within them.
The other reason behind this animation relates to the way in which Chrome manages resources on your computer. When memory runs out, Chrome will "discard" inactive tabs to stop your computer grinding to a halt. These audio icons should mean it now knows exactly which tabs to close so your music doesn't stop playing, for example.
If you want to see the audio icons in action, or if you're the sort who likes to play music through browser windows, then the latest build of Chromium - an open source browser that uses a lot of Chrome's code - is downloadable here.
This could prove particularly useful if Spotify ever turns itself into a browser based player. For us it makes building music playlists on YouTube in Chrome now a viable option, because the app wont dump the audio when you have too many tabs open.