That's what the iPhone is if a user takes out its SIM card or swaps it for an inactive one. Of course, the $500 to $600 device is a very pricey WiFi-enabled iPod, but apparently to strip the phone down to this level a user simply needs to remove the SIM card or swap it for an inactive one. The phone will no longer function as a phone, unless wVoIP counts via the phone's browser, but the WiFi works fine as do the rest of the features should the SIM be removed.

For a brief write-up on the step-by-step:
- check out this article [1] from Tuaw