My collection of PHP classes. At the moment contains following classes:
Classes for generating iCal-files.
Classes for internationalization. Mainly for translating strings. Translationstrings can be stored in different backends (like MySQL, Text, …). Since there is an interface you can create your own backend too. Further there are methods for converting measurements, currencies and numbers.
Same purpose as the RSS Builder only for creating Atom-feeds. In general I would use the Atom format since it's implementation is much cleaner and done after the specs. The RSS Builder classes were build by reverse engineering RSS files.
These classes can generate thumbnails of images and cache the smaller versions. Also you can use other small image as watermarks to place them over the original picture. Further you can create a contact sheet for a whole folder with pictures.
Since I'm a lazy bone, there is not much documentation for the classes. All of the downloads contain example-files which are documented inline and use all of the functionality of the classes. You should be able to understand how it works by looking at those files.