According to Erica Sadun at TUAW, the iPhone can be used with an old SIM card. She activated her phone, then popped out the SIM card and put in an old one. The iPhone continued to function as an iPod, plus web and email via Wi-Fi.
However, I’m pretty sure this won’t work with an unactivated iPhone — and in the comments someone noted that it’ll likely get disabled when iTunes checks for a software update.
Leander Kahney is the editor and publisher of Cult of Mac, and author of three books about technology culture: Inside Steve’s Brain, the New York Times bestseller about Steve Jobs; Cult of Mac; and Cult of iPod. Leander has written for Wired, MacWeek, Scientific American, and The Guardian in London. Follow Leander on Twitter @lkahney and Facebook.
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