> Jeff, I have unlocked Nokia 5610
> (http://www.nokiausa.com/find-products/phones/nokia-5610-xpressmusic),
> which I'm keeping as backup unit.
>
> It was unlocked by T-Mobile, and I used it in Europe. It's quad-band,
> so I should work anywhere.

It should be pointed out that T-Mobile will unlock any of their phones
on demand, just call them and ask for the unlock code. I've done this
for the last three of my phones whenever i am about to travel
overseas. To the best of my knowledge the other GSM carrier in the
USA, ATT/Cingulair, will not.