The CobWeb Framework is a proof of concept php rapid development MVC framework.
It is very flexible, extensible and easy-to-use.
Features: Database Abstraction, Multi-Language, Caching, Script Debugging, URL Routing, MVC Support
RAD object oriented php framework for writing extendable and reusable code. This php framework includes statefull event-driven mvc engine, ORM, DB abstraction and class library for common tasks. Application is a set of classes assembled in an XML file.
Outlet is an opensource object-to-relational mapping tool for PHP. It provides transparent, unobtrusive persistence and is also very lightweight, only a handful of classes and tools.
Kode Monkey is a multi-application/multi-database MVC framework in PHP. It is intended to be used as a Many Sites One Framework platform. Built for Speed of Development/Speed of Use, Kode Monkey is sleek, small, and built to withstand enormous traffic.
Bedrock is a web framework designed around bridging popular APIs and technologies with PHP. While it has an MVC core with all the functionality expected from a web framework, it's primary goal is to simplify the use of other technologies with PHP.
Free open source PHP5 framework for small to midsized projects. Supports abstraction for MySQL, SQLite, PostgreSQL, and MsSQL database servers including in conjunction with the O/R mapping automatic schema synchronization.