That is my own theoretical third stage "fixed up" version of the nasty internet distortion generator "amp" circuit, as posted in the OPs other thread.
If it has ever appeared elsewhere, someone has stolen it from this site!
I keep meaning to build it and see how it actually works, but I just have too much else work-wise and too many other projects queued up at the moment...
The two amp circuits you linked to use two rather different configurations, the Leak design uses the same type transistors (as in PNP/NPN) and the Hacker uses opposite types.