Looks like you can get 100Gb NICs for servers e.g.
https://www.hpe.com/uk/en/product-catalog/servers/server-ada... (Intel, Mellanox etc also seem to have their own)
On the distance, there are other specs that support 100Gb up to 20km on there!
On the distance, there are other specs that support 100Gb up to 20km on there!
Edit: I think you're referring to omnipath. Should be clear than Intel has no 100gbe card available. That link is also pcie3x8, so it can do a max of ~60gbps to host.
Not too unreasonably expensive - roughly in line with a GeForce 1080, and that's after the Official HP Hardware markup. I wonder how much the switch/cabling is...
Do people really do this?! (I don't have DC experience, serious question)