You can use your GPU rig's CPU to mine MHC coins.
It requires just a little % of your CPU to run the
Metagather app.
No open ports or such needed, just a 24/7 running PC. They will lend you the first 1000 coins
so you can start earning your own
MHC coins.
Tried this out.
For first 1000 coins - "you are 11 in the queue" wtf? "keep your wallet to receive faster" i don't understand.