iphone 4... use without activation?

I'm sure you can, all you need to do is put it in airplane mode.

After an iPhone is activated, it can be used as an iPod Touch after being deactivated. In order to restore a no longer activated iPhone with iTunes or to install a firmware update on a no longer activated iPhone, the no longer activated SIM card must be inserted in the iPhone in order to complete the process - the SIM card that was used with the iPhone when it was activated.

Not entirely true. At least with AT&T, you can use ANY AT&T SIM card, when activating it. It can be a brand new, not-activated one, an active AT&T SIM that is not connected to the account that the iPhone was ever on, or someone else's inactive (used and deactivated) SIM that's an AT&T SIM.

Doesn't have to be the same one you used with the iPhone. And I have tried and verified this.

Nothing I provided has anything to do with activating an iPhone.

Allan Sampson wrote:
Nothing I provided has anything to do with activating an iPhone.

The following refers to activating an iPhone, which you HAVE TO DO after restoring an iPhone.
Activating, as in activating the iPhone (which iTunes even states once the restore is done and when the iPhone reboots. Not activating as in putting it on the network.

Allan Sampson wrote:
In order to restore a no longer activated iPhone with iTunes or to install a firmware update on a no longer activated iPhone, the no longer activated SIM card must be inserted in the iPhone in order to complete the process - the SIM card that was used with the iPhone when it was activated.