Out of curiosity,

Anybody here operate internet gaming cafes? That's the only business I can think of that would have a bunch of GPU equipped computers lying around that weren't bought as part of a computing cluster.

Make money from games and printing during the day. By night reboot into linux and run a GPU mining cluster...

Wish I was in that business.

I don't think they'd mind as long as you split the profits. You should talk with them first though, as I've had more than one person ask me, "Are you sure this is legal?". I do computer repair on the side, and I'm using the profits from my work PCs to help pay for expanding.