a coin for circulation, and it can't be Litecoin either, because it's too rare for that, just like Bitcoin
There will be nearly as many as 21*10
12 microBitcoins, on average it's about 3000 per every human being on the planet, and every microBitcoin is still dividable to 100 pieces.
Nobody gives a flying f*ck for micro. People want whole coins, not some microsh*t parts. That's why Dogecoin is getting more and more popular.