Of late I have become Addicted to Flickr. I love photography so its great to have an easy way to show your photos off. I am also very interested in Web Services. I checked out a few of the API kits suggested on Flickr but two use PEAR and the other requires PHP5. I love PEAR but some people have problems getting it working on shared hosts. Plus, I wanted to learn something new so I started creating Addicted to Flickr. Addicted to Flickr is a PHP class which aims to make it as easy as possible to use some of the Flickr API methods that I thought would be most useful (the ones not requiring authentification). It makes requests to Flickr with CURL (CURL class written by Dick Monroe) by default (uses fsockopen if CURL not available) and caches the requests in a database or on the filesystem. I know nothing about licenses and don't really care to. Use this however you want, but I would appreciate it if you would let me know (because I would love to see it in action elsewhere).
The best way to help make this class great is by testing it. I have tested, but I am an army of one. Download this class and try it out. If you get any errors or anything doesn't work properly, let me know. Also, another way you can help is with feature requests. If you have a feature request, you can leave a comment with the original article or use my contact form. Also, you can always donate.
Each Addicted To Flickr method in the documentation has a code sample, the XML response returned by Flickr, the array returned by the function and a sample of what the XHTML could look like. I don't list all the function parameters as I have well documented the actual class file.