AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
Authorize.net is a secure online payment gateway service that enables businesses to accept payments through various channels, such as ecommerce websites, mobile devices, and retail stores, providing a trusted platform for processing credit card and electronic cheque payments.
Google Analytics is a free web analytics service that tracks and reports website traffic.
Prototype is a JavaScript Framework that aims to ease development of web applications.