I'm in a major city (so coverage is good on most networks), but T-Mobile has a $30/mo, pay-as-you-go plan for unlimited text/data and 100 minutes of talk (which isn't a problem if you use something like Google Voice).
I was under the impression it was 5GB 4G then 3G from there, but it is not so.
[1] Like https://play.google.com/store/apps/details?id=com.snrblabs.g... or https://play.google.com/store/apps/details?id=com.moplus.gvp...
https://play.google.com/store/apps/details?id=com.google.and...
I had to deal with this problem earlier this month, and the answer here fixed the issue for me: http://android.stackexchange.com/questions/44677/how-to-chan...
With regards to one of the up the stream comments, I love the T-Mobile $30/mo 100min, unlimited text, 5gb 4g plan on my Nexus 4.
https://play.google.com/store/apps/details?id=com.gvoip&hl=e...