I don't think 1000 dollars or so for an iPhone is an issue of concern -- some people will spend thousands of dollars for it on eBay. The question is though: Where can I get it unlocked and without service plan and, most importantly, will it work in Europe -- with a German provider, to be precise?
Once unlocked, it will work. The question will be, "
How does one unlock the iPhone?". With the Treo, it was possible to get Cingular reps to unlock them with a little coaxing. "I
travel international...roaming charges are expensive...would like to use a SIM card in Europe..etc". A number of people I've seen on the Treo forums have had success with this method. Because Apple is involved, I don't see this happening. I think Cingular/AT&T will put the clamps down on the iPhone and CSR's won't have the ability to unlock.
I'd also suspect we'll see a lot of eBay scams offering information on how to unlock the iPhone. If someone does figure it out, then expect them to command a nice chunk of change.
-Chris