I have started the agent, built from the design described on this site. The agent consists of modules, that communicate through signals. The agent uses a simple triple store (built on top of a MySQL database)  to store its data. The web application makes sure each user can login and gets assigned his/her own agent. The web-app performs an ajax request two times per second to activate the agent. Each ajax call, the serialized agent for the current user is loaded from the triple store and it is deserialized. It's "process" function is called, that allows all its modules to process incoming signals. And then it is serialized again. I now have working an agent that sends a signal and this signal is processed only the next iteration. This is pretty cool. But, thus far the agent still does absolutely nothing :)