DB_eSession is a feature-packed PHP class that stores session data in a MySQL database rather than files. It is powerful, designed with security in mind, and is easy to utilize. The code contains lots of comments, and it comes with full documentation and examples of how to use the class including a basic authentication login/logout process. It includes member functions useful (to webmasters) for monitoring or viewing, deleting, and altering sessions validity for the case of locking one or more sessions upon detection of unauthorized use.
The Enhanced File Crypt/eXtended File Stealth System (EFC/XFSS) makes your uploaded files safe on the server so that no one can read them without knowing a few details to decipher the files. It generates different obfuscated names and encrypted files so no one will know what the original format or name was.
File-Picker is a program to display and choose files from your Web site. It supports multiple languages. It uses AJAX to allow the user to interact with the server without reloading the page. You can pick several files at the same time. Its visual interface looks like a file explorer.
MobileUserAgent is a PHP class which parses user agent identifier strings from browsers used by mobile devices to extract relevant information. It recognizes many of the current mobile user agent identifier strings and processes them to extract their basic constituent parts, the most important being the mobile device vendor and model.
YourPay is a PHP class that can be used to submit WorldPay transactions through a WorldPay account without the very impersonal payment pages provided by the said company. This class will submit the user's credit card details in real-time and return either "Authorise" or "Decline" according to the response.