Well I decided that it is high time my robot can see the world for what it is.....or at least for what 4 LDRs setup on voltage dividers can reduce to a voltage range picked up by the AVRs built in ADCs :P
Using LDRs that I think I got from Futurlec I soldered a 100k ohm resistor to one leg. Now if you apply 5V on the free leg of the resistor, zero (Ground) on the free leg of the LDR you can read a reliable 0.7V to 4.2V range from GND to the soldered leg of the LDR.
Now I am going to put them on a Servo facing away from each other. With 180 degrees of servo rotation, I can rotate sensors to calibrate from each other's readings (assuming the environment doesn't change the light conditions in between servo movements.