Portable power - what's your solution?

I know a lot of people here are into small portable rigs, with the OP-1 at the centre of them (of course!). It’s something I’m looking into and I noticed this Kickstarter campaign which seems to offer one solution for portable power, particularly with a USB battery (though you can power it from your phone and other ways too):



What’s your solution for powering your small portable rigs?

I’ve already got a couple of adaptors from myvolts, creators of the ripcord. One for my Circuit and one for my Volcas. Got a USB battery pack with 3 ports to power them. Great in theory but more than one adaptor per pack and I have dreadful ground loop issues. So just get more than one battery packs.