As username! said, deacons do a bunch of stuff! Liturgically, they are attached to parishes, to cathedrals (and therefore to the bishop, like the protodeacon who travels with his bishop to serve) but they can do other stuff, too. Just like priests serve as chancellors to a diocese, or as deans to deaneries (in some jurisdictions), deacons also have administrative functions they pick up. Everything from diocesan treasurer/secretary to webmaster to who-knows-what-else. These positions don't HAVE to be filled by deacons, but they certainly can be.