https://www.theregister.co.uk/2018/05/25/seagate_batterypowered_virtual_reality_drive/

VR folk who feel they haven't got enough gear strapped to their bodies will be please to know Seagate has developed a strap-on portable drive and battery combo for HTC's Vive Focus virtual reality headset.

The VR Power Drive has 1TB of capacity and a 5,000mAh battery hooked up to the headset with an integrated MicroB cable and USB-C adapter. It comes with a clip to fasten it to the user's waist belt.