Some weeks ago I looked at some configuration management tools like chef, puppet and salt, but I gave up when noticed that a server side agent was required.

Fast-forward to this saturday, at the hackmeeting there was a talk about ansible, a tool for this purpose written in python. I didn't attended the talk but today I looked the website

Ansible is a radically simple IT orchestration engine that makes your applications and systems easier to deploy. Avoid writing scripts or custom code to deploy and update your applications— automate in a language that approaches plain English, using SSH, with no agents to install on remote systems.

That looks really, really good, I'm testing it now and works great, it may be what you where looking for :P.