My PDA is walking library of first aid, preparedness, and survival knowledge. On it I have:
Detailed maps of the quad-county area from "Mapopolis".
"Biochem 1.6" a program to identify and treat all sorts of chemical and biological threats.
"Torch" which allows me to use the PDA screen backlight as a very weak flashlight.
"COMPASS" which automates the old "wristwatch-sun " finding north trick.
iSilo documents (reader program) covering first aid, KI dosages for nuclear incident, riot gas treatments, five articles on guns/self-defense/gun facts, assorted docs on water finding (urban and rural) and treatment, disaster kits, map-compass use, pet safety, making moonshine, US-Army survival manual FM 21-76, and a list of useful shortwave radio frequencies. I also have assorted contect information for neighbors, friends, family (mine and in-laws), and co-workers.

I use "Print-Boy" and "IR-Pad" to beam and print documents straight from the PDA directly to any IR equipped printer. An occasional trip through CompUSA to test printers gives me my paper back-ups. <img src="images/graemlins/grin.gif" alt="" />

Then there's the usual personal information such as car makes, models, license plates and VIN numbers in case they are stolen. Blood types and any prescriptions of all family members. Insurance data, vet info, and assorted emergency phone numbers. Our area is prone to flooding so I have a checklist of what needs to be moved upstairs, who is responsible for taking it there, and where exactly it is supposed to go upstairs.

I have backups of all this data, both dead-tree and digital. It's a pretty extensive library, but other than the maps it doesn't use up that much memory on my Handspring Visor.

-Blast