When a person has a small, minimally furnished apartment, and low quality car, because they spend all of their money on all of the newest high-end electronics.
These can include T.V.'s, sound systems, computers, cell phones, etc.
Similar to the concept of being hood rich.
Jeff: "I thought Andy landed a high paying job. Why is he still living in an apartment and driving that Geo?"
Tom: "He can't afford them man, he's totally geek rich."