I doubt if many individuals would run it on their own hardware. They're more likely to run it in the cloud. I know someone who set one up the other day on Amazon's AWS S3 - he's expecting it to cost a few dollars a month for his trial server. If it got big then the storage cost might be considerable - all those cat pictures!
The trouble with running your own hardware - even if you have a server lying around - is security, firewalls etc. It'd get attacked immediately.