Clickable Tooltips in jQuery UI
Another 15 minutes of fiddling, and you can see my complete solution here: http://jsfiddle.net/abbylangner/XHb4Z/.
The primary issue that sent me searching for another solution was the requirement for links and other dynamic, clickable content within the tooltip. An answer from StackOverflow got me started. It just needed a little extra tweaking to make it reusable for the variety of custom tooltips on our page.