vBulletin is a powerful, scalable and fully customizable forums package for your web site. It has been written using the Web's quickest-growing scripting language; PHP, and is complemented with a highly efficient and ultra fast back-end database engine built using MySQL. vBulletin is the ideal community solution for all medium-to-large sites.
Homepage:http://www.vbulletin.com/

PHPCart is a simple shopping system for small web-merchants. Set-up of PHPCart is quick and easy, and does not require a database. You can use your own header and footer, change colors and choose between several languages. Adding your own language is easy if it is not already supported. v3.1.4 now supports 18 different Payment Gateways so you can offer a number of payment options to your customers and have them processed instantly upon submission of payment form.

BlogHoster is a PHP-based software product which allows you to provide a blog hosting service on your website. The blog hosting that you give your users with BlogHoster is comparable to popular third-party blog hosting services like Blogger, Livejournal, and Typepad. As the admin of your blog hosting service, you can control how users will signup, write in their blogs, and interact with each other. The entire visual frontend of the software is generic, so you can easily give it your website's look and feel. You can even have ads automatically inserted on your users' weblogs. BlogHoster also includes a variety of social-networking features, including interactive profiles, photo albums, friendships, blog categories, and more.