»We have met the enemy.

Mobile Infrared Devices, or MIRTs, allow non-law-enforcement to arbitrarily control traffic lights. While this was an entertaining plot wrinkle in The Italian Job, it doesn't really scale for the antics of commuters.

4 November 2003 UPDATE: This is all over the news right now.

And the antics of a commuter stopped the Metro-North commuter railroad:

The man was on a suburban train from Grand Central Station on Wednesday night when he went to the bathroom to make a phone call, dropped the phone into the toilet bowl and then his hand and arm became stuck trying to retrieve it, officials said.
Metro-North Railroad staff could not help the man, so they stopped the train and called police officers and firefighters to extricate him, a process that took 90 minutes using "jaws of life" rescue equipment.
"The toilets are made of aluminum so I imagine he was down on hands and knees with his shirt rolled up and hand and arm down inside, trying to flush out his cell phone," said Jim Cameron of the Connecticut Metro-North commuter council.

You can build your own gyroscopic human transporter á la Segway or Ginger or the "IT" thing or whatever.