Thank you lallafa for continuing to update this.
I built one for my 2000 a bit back using the pollin avr kit (I thought i had orderd the module but my german sucks so I had to solder it together and program the blank bootloaderless avr with a arduino as a isr etc).
I mounted it inside the 2000 case by desoldering the parport and putting a header cable on and mounting the box inside the case with just a rear ethernet port. Its been plenty fast enough for what I need ethernet on a 2000 for and I power it off the 5v available inside the case from the original psu having done the jumpers instead of diodes and a link over the 7805 reg.
Theres a suitable case for the pollin boards on thingiverse if people have access to a 3d printer. I printed the lower half twice but mirrored for the lid as the thingiverse one also has space for a lcd which I didnt need but I coundn't be arsed redrawing it in cad without.
I use mine with amitcp, I shall read up tomorrow if I can use this release once sober and reflash my avr with it.