You'll actually have to go to .sh among the contenders (this is what I would suggest) as .io is not up anymore and besides .me was the original one.
It's linked on the official/original github repo[0]. But the official official[1] repo doesn't link anything. Just that original developers are supporting .sh as official and have apparently moved to it.
There's also ...ce.ch but that's community edition as the last two chars suggest.
https://en.wikipedia.org/wiki/Joseph_Nacchio