Gritter is a jQuery plugin for creating Growl-like notifications with ease.
The notification bubbles created looks very similar to the ones in Mac OS X & they can be styled easily if wanted.
It is possible to create multiple notifications where each of them can be controlled with their unique IDs.
They can be set to disappear automatically after x seconds or stay until removed manually with the “sticky” option.
You can also mention the speed of the fade effect used while the notifications appear/disappear.