creating a gallery of a bunch of images: 

* Display Exif informations
* Display Image informations (like size, date, resolution, compression...)
* Create CSS data for customizing
* Create Thumbnails (maybe in more than one size, eg: full,1024x768,800x600,640x480)
* Descriptions for every image
* Comments
* Ratings
* Watermarks
* Some javascript for easy navigation (see [photon](http://www.saillard.org/programs_and_patches/photon/) for a good example)

It should be possible to disable every feature for every directory.