NaturePHP is a classes wrapper using PHP's autoload to create a non-intrusive, simple, organized, and extensible library system. It is aimed at intermediate and advanced PHP developers, providing a lot of non-intrusive functionality for Web site and application development. Upcoming development will include internal library management and the ability to download/update libraries from the repository.
PayPal Payments Pro/Adaptive Payments PHP Class Library includes methods to easily integrate all of PayPal's APIs, including PayPal Payments Pro and Adaptive Payments. It makes it extremely quick and easy to tie PayPal into your applications. It comes with template solution files for nearly every API call available. All you have to do is populate the request parameters, and you'll get a PHP array result which includes everything you'll need from the API call.