@vim_user and smitty
Those ideas did cross my mind, but I guess it comes down to how much more cost effective ARM is compared to using a retired high-workload server or just simply a low-end AMD server.
As another quick question - do any of the 64 bit ARM systems allow replaceable memory, or is it all SoC? I could see a use for ARM in a server market if the 64 bit models allow regular DDR3 DIMMs or SO-DIMMs - sometimes tasks are very memory demanding but not so CPU demanding. I suppose ARM would also be handy if it were used as a central backup system, assuming some of the server models have bundles of SATA/SAS ports.