Perhaps consider what types of emergency you want to survive? That will determine your choice of equipment. In most situations, you don't have to worry about food or water, at least in the short term, if you're in an urban environment, as long as you have money. Anywhere you go, a cell phone with a backup battery seems like a good idea.

Below I is my cursory response. Please correct and add as necessary.

Common emergencies:

Medical (car accident, sickness, assault, etc.) -- If you are flying, I don't know that you can carry much more than a basic first aid kit, which is probably going to be woefully inadequate. Cell phone for calling 911.

Fire -- Some sort of mask/bandana for the smoke. Flashlight. Cell phone can serve as a light source, too. Also, know where the exits are!

Transportation outage/disaster -- Flashlight, FAK. If you survive the initial event, a pair of walking shoes and money will eventually get you back to your hotel. Some sort of map

Power outage -- This could be cell outage or internet outage as well. Flashlight, FAK... What else? I'm drawing a blank.