I know this is going to sound a humongous task and many of you would think why in the world would you want to do so or why re-invent the wheel. However I just want a project I can work on the side see how it goes and experiment ( I got a thirst for learning something new and this is a great challenge).

Question

Where would I start creating a server-side scripting like php, asp and (now) node.js

I would like to have a few examples, and most importantly a CODEX/documentation where I can learn and find out more how it works.

I guess I am asking for directions where to go to read and find out more about this.

Many thanks,