Just want to capture the word before it goes mainstream (if it ever does):
The act of virtually participating in a different virtual or physical space than the one you physically inhabit.
includes Teleparting, 'parting, and "part in".
Portmanteau of tele (ancient greek, "at a distance") and participation.
You read it here first.
(yes, I'm aware there's search hits, but they're all mis-speeelings of teleportation)