Hi Burnie,
I have used several meters with no problems. Would use 5 Volts to power them (not parasite power). The voltage drop is only quite small because of the very low currents but use cable of twisted pair and/or shielded, eg; Cat5, you must avoid any induction/noise from high voltage sources running nearby. I used 100mA quick blow glass in-line fuses to protect the circuit in case of a short occuring due to any damage to cable run or sensor. You could experiment by connecting up the sensor with clips to the end of a long length of cable coiled in the same room. There is more info if you go from this page to home/links/Peter Anderson/ scroll to sample routines/a three point monitor using DS18B20. He quotes success using 200 ft of cable. Anyway, as the others say- let us know how you go!