Grumble.js, a jQuery plugin by the developers of Huddle.com, enables us to create tooltips as bubbles.
The positioning of these tooltips are very flexible and, with the help of “angle” and “distance” settings, they can be pixel-perfectly placed (by using CSS3 transforms and Matrix filters for IE).
Bubbles come from a sprite image and the plugin decides which image to use according to the size of the text.
Tooltips are displayed with a fadeIn/fadeOut effect, can be set to auto-disappear or stay visible until they are closed.
There are also callbacks on every level: