SHARE wrote about zenphoto gallery. He siad that he tried many (all?) opensource photo galleries for personal needs: Gallery1, Gallery2, jAlbum, Coppermine, you-name-it and settled on ZenPhoto a few months ago.

ZenPhoto is a lightweight, ajax-ish opensource software that provides uploading, managing, describing and commenting of your pictures. It does so with a relatively spartiate interface, leaving the (useless) bells and whistles to the competition. It also uses a very easy CSS templating system, so you can modify the look without pulling you hair out.Its possible to integrate it with WordPress through the use of both a plugin and a php hack.
The latest release of ZenPhoto is 1.05 . Recommended for everyone!