Me and one other guy on these forums received and "extra" iPad Air when it was released upon signing up for AT&T's Next plan. When ATT was contacted, the CSR simply suggest to keep it. Said they didn't know how to put it back in the system lol. True story! Sold my extra and bought a iPad Mini Retina for my wife, with the expectation of being billed eventually. One year later, nothing.
I'm not sure if this answers your question, but you can get an external hard drive that creates its own wifi network. Sandisk and seagate as well as some other companies make them.