PHP On Pie is a PHP framework that combines the best ideas from PHP projects like Drupal, CodeIgniter, Kohana, and ZendFramework. It has very few core concepts: classes, models, events, slots, and tools. It lets you repackage completed apps into plugins that you or others can use later. Its smart database classes allow you to implement vertical and horizontal partitioning (sharding) easily to handle millions of users.
Nitro is a really easy to use, very customizable, and extensible ORM for CodeIgniter. It's pure PHP, which means you won't have to install any commandline tools to run it, just one mapping file (or as many as you like), which is as simple as defining a PHP array, and let Nitro create the classes and manage the relations.
FSP is a UDP-based protocol for transferring files. It has many benefits over FTP, mainly for running anonymous archives. It is usable on lines with high packet loss ratio (70% WiFi), can go behind firewalls and unnoticed by port scans (because of UDP), does not overload networks when hosting ISOs or movies, share files on modem lines without eating all of the bandwidth, and keeps lamers away from your site (they don't know how to get to it). This project is active continuation of the FSP code base (abandoned 1996-2003).
StringParser_BBCode is a PHP class that parses BBCodes with a real parser and not just regular expressions. This ensures that the HTML elements are correctly nested. It does not define any special codes, but allows the programmer to do so herself. It provides many features, such as the automatic detection and handling of paragraphs and the ability to apply different so-called parser functions to different portions of the text that is to be parsed.
muhttpd (mu HTTP deamon) is a simple but complete Web server written in portable ANSI C. It supports static pages, CGI scripts, and MIME type based handlers. It drops privileges before accepting any connections, and can log received requests. It has been tested on OpenBSD, GNU/Linux, NetBSD, FreeBSD, Mac OS X, and Cygwin. It runs successfully on 32-bits, 64-bit, little endian, and big endian systems.