[jQuery] How to select last leaf of a tree?

[Matias]

Hi,

I have an unordered list like this
<ul>
  <li>Item 1</li>
  <ul>
       <li>Item 1.1</li>
       <ul>
           <li>Item 1.1.1</li>
       </ul>
  </ul>
  <li>Item 2</li>
  <ul>
       <li>Item 2.1</li>
  </ul>
  <li>Item 3</li>
</ul>

and I want to select only the leaf nodes (in this example namely Item
1.1.1, Item 2.1 and Item 3)

I was wondering if there was an easy way to use jQuery selectors to
perform such selection? What would be the simplest way to do it?

I'm able to do the selection with a combination of selectors and
javascript in callbacks, but as I'm always willing to develop my
skills, I thought I ask the gurus.

Thank you.