Here's what I've done:

    - Unlocked iPhone 
      (I bought a Canadian one, but you can also jailbreak.)
    - Clear 4G mobile hotspot

Between this and onsite WiFi, I have all the mobile broadband that I'd want.

After reading the article, I'm considering moving from my T-Mobile monthly service to AT&T GoPhone. I can buy minutes and megabytes for emergency use and maintain this for very little cost. (Which I'm free to do, since I've refused to have a contract.)