Flickr Tag Cloud

Josh wrote a Flickr Tag Cloud Widget for showing off your photonomic prowess.

Flickr

Ben wrote an advanced Flickr widget that gives you lots of control over which photos you display.

APOD

Astronomy Picture Of the Day, now available as a WordPress Widget. Get the APOD Widget. (It’s cheaper than a telescope.)

Gallery 2 (WPG2)

Javier has put together a couple of widgets for WordPress Gallery 2: Random Image and Grid Block.

Picasa Web Matrix

If you’re lucky enough to be a tester for Google’s new Picasa Web Albums, Stephen’s Picasa Web Matrix widget will display random thumbnail images from your web albums.

WordPress.com Flickr Widget

Donncha has packaged and released the Flickr Photostream Widget popularized here on WordPress.com.

Coppermine

From Robert Oddy, here is a sidebar widget plugin that displays a random image from your Coppermine photo album.

Lazyest Gallery Thumbs SlideShow

I found Tash Bolta's Lazyest Gallery Thumbs SlideShow PlugIn via the RSS widgets in the sidebar here.

WPG2 ImageBlock

WPG2 ImageBlock is another widget plugin from Matthew Holger. This widget enhances the popular photo gallery plugin for WordPress, WPG2, by allowing you to move and change the title of your Gallery Image without editing your theme.