<p>I develop a number of desktop Java applications using Swing, and while Swing is quite powerful (once you get the hang of it), there are still a lot of cases where I wish some advanced component was available right out of the box.</p>

<p>For example, I'd really like to see easy-to-use components (without writing them myself, which I could do given enough time) like:</p>

<ul>
<li>Multi-line label</li>
<li>Windows File Explorer-like Icons or Thumbnails view</li>
<li>Drop-down button (like Firefox's old Back button)</li>
<li>5-star rating widget</li>
<li>Combo box with automatic history (like the text field on Google)</li>
<li>An Outlook-style accordion-style bar</li>
<li>and so on</li>
</ul>

<p>I know of a couple of sources of free Swing components, like <a href="http://swinglabs.org" rel="nofollow noreferrer">SwingLabs</a>, home of JXTable, JXDatePicker, and a few others.</p>

<p><strong>Where do you go for Swing components beyond those included with Java itself?</strong></p>

The following are worth a look:
swingX
Glazed lists
Substance look'n'feel
Flamingo components
Ken Orr's Mac Widgets
Jide's open source components