I remembered reading about this several years ago and was able to find it:
Eternal 5D data storage via ultrafast-laser writing in glass (spie.org)
Huge capacity
Zero power usage while not being read
“ultrafast” write speeds
Read-only medium perfect for plots
Decay time comparable to age of universe 
Apparently some flies with Starman! Optical ‘Superman’ memory flies with orbiting Tesla (optics.org)
Sounds expensive, “reaches for visa”
The laser-etched quartz is amazing for its durability and passive nature, but not so much its storage density even relative to flash cells and HDD platters.
Keep an eye on DNA data storage – the molecular helix is 2nm in diameter and highly stable in liquid solution, making off-the-charts information density possible.
The DNA in a single human body – disregarding everything else a body does – has a data capacity easily exceeding the total of all HDDs ever manufactured to date. (Roughly 1 GiB per cell, 30 trillion cells)
Well this single human body has the short-term memory of a goldfish and has already forgotten way more than it has ever remembered, so I’m not putting all my money on bio storage yet. 
