EU train travel on a budget?

I would like to travel around Europe for a month but am struggling to figure out a way to do so withoout spending all of my savings. Are there multipass EU train passes for non students I oculd consider, on a train service I can sleep on the train and jsut get off and on at any country and city in EU for a month? I thought that would save me the hassle of looking for places to sleep and would save maybe on accommodation expenses? I'v looked at Raileurope and a Erurostar from london to paris will set me off at �200. Is it possible to travel for a month like this, on a budget of �400 ? Please I would appreciate some advice as I assked a travel agency and they didn't know and I looked at seat61. thanks