Cost-Effective Server Room Air Conditioning?

at0mic26 writes "I am currently tasked with finding a cost effective solution to our 30+ degree Celsius server room. The only air conditioning currently provided is a single duct pipe from one of two air conditioner units. I was thinking of stealing air from the second air conditioning unit with some sheet metal work, but it likely will not be sufficient — and would not have tolerance for both AC units being offline for any amount of time. An ideal supplemental portable AC unit is what I am after, however I'm finding it cost prohibitive, with $600+ humidity controlled AC unit, plus 20 amp socket requirement, plus contract work to make a hole in the wall for outside drainage so that the unit does not flood the place. What sort of successful cheaper air conditioning solutions have you come up with?"