There was at least one model of Dell switch that used HDMI for 10G connectivity a few years back, so it seems doable. I think most people looking for cheap and

There was at least one model of Dell switch that used HDMI for 10G connectivity a few years back, so it seems doable. I think most people looking for cheap and fast home networking end up going TCP over infiniband, which is a project I've been meaning to look at sooner rather than later myself. You won't touch 120G though, but I don't think you'll find disks that fast anyway.