python-fedex is light wrapper for Fedex's Web Services SOAP API. The intent is to stay out of the way of the developer as much as possible, while handling some of the more repetitive and mundane portions of forming and sending SOAP requests. The module makes use of the excellent suds package along with Python versions 2.5 and up, but not yet Py3K.
Ripcord is an PHP 5 XML-RPC server and client library with a very simple and easy to use API. You can create XML-RPC, (simplified) SOAP 1.1, and SimpleRPC clients with one call and then call RPC methods as if they were local methods of the client. You can create a server with one call, passing it any number of objects or classes whose methods it will publish and automatically document.
Magento API Client is a PHP client library for the Magento SOAP API v2. It supports the Mage_Catalog, Mage_CatalogInventory, Mage_Checkout, Mage_Customer, Mage_Directory, Mage_Sales, Enterprise_CustomerBalance, Enterprise_CustomerGiftCard, Mage_GiftMessage, Mage_Core, and Store_View modules. The library uses namespaces and is based on composer tools.