What is the simplest ORM implementation around for PHP? I'm looking for something really simple and light (in terms of LOC, since speed it's not crucial I don't need caches and what not), preferably a single file or class package that doesn't depends on XML or other configuration files and it's easy to deploy.
Reading other similar questions Pork.dbObject (which by the way is developed by one of SO users) was the closest I could find so far, and I'm interested in knowing if there are any other ORM implementations that might be lighter than this one.