AddThis is a social bookmarking service that can be integrated into a website with the use of a web widget.
Apache is a free and open-source cross-platform web server software.
Websites that have a shopping cart or checkout page, either using a known ecommerce platform or a custom solution.
Carts Guru is the all-in-one marketing automation tool for ecommerce stores.
PrestaShop is a freemium, open-source ecommerce solution, written in the PHP programming language with support for the MySQL database management system.
reCAPTCHA is a free service from Google that helps protect websites from spam and abuse.