I want to build a mobile phone with the following hardware sensors:

Accelerometer
Altimeter
Ambient Light
Anemometer
Barometer
Camera
GPS
Hydrometer
Laser Range Finder
NFC
Magnetometer
Thermometer

I then want to mash all the readings together and collect other abstract network-sensed data like signal strength, infrastructure IDs, and transaction types. I'd then have lots of fun with GIS, BI, spatial statistics, modeling, and analysis. Wow, that would be fun!