Regarding Packetstream Gold, yes, it will work.  The service is basically an
implementation of Mobile-IP (as in Internet Protocol) which is what is used
for the browser service.  Be aware that two downsides of the PG product.
One, it only offers a non-routable IP address, so you can go outbound
through Nextel's gateway to anywhere on the public Internet from the phone
and work once a connection is established through the gateway.  A server
somewhere on the net won't be able to initiate a connection to you, though,
because of the non-routable address.  Nextel does offer a routable IP
address on their Total Connect service (which is a metered, per byte sent
service).  Second caveat, there are "terms and conditions" surrounding the
"unlimited" PG service.  Nextel reserves the right to boot you off the
network if you abuse the service.  Examples of banned services, high
bandwidth streaming applications, telemetry applications, etc.