I doubt heat from the cpu would be a big problem.

It's not just CPU heat (there are three CPUs in this case) there are also two IDE hard drives and six SCSI hard drives. My current setup manages to raise the temperature of an reasonable size room by 10 degrees compared to the rest of the house. I was surprised at this too.

Then just route one of the ac ducts thru the box on its way to any room you choose.

Unfortunately, like 99.99% of houses in the UK, there is no aircon. I am considering getting a portable AC unit for my office this summer though (if I haven't moved the servers elsewhere), I am worried that it might be expensive to run though.