qdgal
Simple and lightweight photo gallery for PHP
...There is plenty of such gallery softwares on the internet, but every one that I checked was too complicated, and I needed something *very* basic. No authentication, no user options, big text (to be used even by older people that are not that comfortable with a computer). I wrote a short script during a summer afternoon, and qdgal was born.
How to use it: simply copy the index.php, index.conf and index.css files to your web server, into a directory where your photos are stored. That's all.
You can optionally edit index.conf and/or index.css if you'd like to customize qdgal's look, but that's up to you.