This "Apple memo" that appeared mysteriously on Fake Steve Jobs' site plans an all-out iPhone attack on AT&T's network this Friday, December 18 at noon Pacific:

Subject: Operation Chokehold
On Friday, December 18, at noon Pacific time, we will attempt to overwhelm the AT&T data network and bring it to its knees. The goal is to have every iPhone user (or as many as we can) turn on a data intensive app and run that app for one solid hour. Send the message to AT&T that we are sick of their substandard network and sick of their abusive comments. The idea is we'll create a digital flash mob. We're calling it in Operation Chokehold. Join us and speak truth to power!

You could join this flashmob to bring AT&T "to its knees," but from what I can tell, it's already there. [Fake Steve]