One other fantastic tooltip library is Poshy Tip. This one’s a bit older but it does support modern jQuery and most modern browsers.
You’ll find a full series of demos right on the website along with documentation for setting up the plugin. These tips do look beautiful but they’re somewhat limited with animations. That’s one reason why Tooltipster stands out beyond this plugin.
But if you just need something simple and efficient Poshy Tip will do the job well.