Oh, I am going to have good fun with this idea...I always, somehow, end up with a Technomancer in my party. Without fail.
An electronic device for storing and processing data, typically in binary form, according to instructions given to it in a variable program.
That's the definition of a computer. Take out 'electronic', and suddenly you have natural formations that can store data. But only in, say, Sperethiel, or Orz'tet, or another obscure dialect with limited understanding in the present. So Stonehenge can be logged into. Maybe it's a complicated simulation of Mana Storms - who said that only 2070 tech could produce UV nodes?