How to emit hair particles from other hairs I was trying to create moss (it's probably not moss, but still), and upon examining a patch of it from close, (IRL), I figured the easiest way to make it would be to have a particle systems that emits hairs, and them emit other hairs from each; however, I can't find a way to do this.

Is this possible (without the use of Particle Nodes, since the latest release was 2.62)?
It is possible to do this non-destructively, but you must be using a mesh object for your first object. 


Add a particle system your base object, then set the Type to Object and select your initial hair object:


Add a hair particle system to the hair object:



The hair particles will also appear on each instance of the mesh object, but only in the render (this is probably a good thing :P).