YES. If you buy the phone at retail price?? The $600, or $300 used. Or if you get it cheaper on your own. Sure you can activate it on a prepaid line. You just won't get the full 5 gig plan. You'll only be able to get the 2 gig pre paid plan. But, you do HAVE to have data on the phone one way or another.

Currently there is 1 Android phone offered at a discounted price with pp service. But, you can activate one you buy on your own just fine. I don't think the same applies to Blackberry or Windows mobile phones though.