Epicenter is one of those trendy startupy San Francisco cafes where people stop by from coffee from their offices nearby in SOMA. They give internet in 2-hour incremenents in paper slip form with a lame web interface to make sure you bought something. Across the street is a building that would make a pretty good bomb shelter, but the coldwar-era sign looks faded since people don't care about NUCLEAR ARMAGEDDON SAFETY much these days. I just heard some people say "or I could continue speculating on bitcoins. I really like bitcoins" so it's one of those places as you might imagine.
It's really annoying to get to epicenter from BART because 4th is one way toward the interstate and Harrison is one way away from Epicenter.