Microcenter had parallel-port line-extenders in their Bargain Bin section for around $15. I think that they claimed up to 100' reach on the parallel port, obviously due to the signal amplification/noise reduction of the device. Normal standard spec, I think goes to about 12'. At least I don't think that I've seen any IEEE 1284 shielded cables longer than that. If they aren't heavy-duty shielded, then I probably wouldn't go longer than 6-8. I've had cable-noise issues when daisy-chaining an inkjet printer through a scanner and into the computer, or when going from computer to a manual switchbox to a scanner or printer. Combined cable length was probably 12'.