Do what? 
Could you use a Tmo/AT&T phone with virgin mobile service?
Personally I don't see what the big damn deal with offering data-only plans is anyway. No carrier seems to want to do it. Which to me says that they've probably determined that it would somehow cost them a lot of money.
I have the cheapest available voice plan on my iPhone, which is $40/mo. It's 450 anytime, 5000 nights and weekends, and unlimited mobile to mobile. Plus the 450 minutes rollover any unused for up to a year. This month I've used all of 1 minute of my anytime allowance, and have like 5,000 minutes in my rollover allowance. But I have used 1.5 GB of data and 300 text messages so far.
