Hmm,

Simply put , Everything or every way anyone makes or receives payments. for any & everything.
Products or Services (real or virtual)

ZEIT is a crypto barter coin , to be bartered for anything someone needs.
It is designed for the entire world's use , not limited at all.

What ZEIT can do is only limited by the world's imagination. 

Examples,
Barter / Payment System
Virtual / real currency in a game or at Casinos
Voting System
Digital Locking system on virtual & real world safes
Way to turn on/off a sprinkler or light system or even software licenses

It's uses are limitless , and how it best serves you in your life, is your choice.