If you're willing to leave the cisco/Arista/etc cocoon, NIC costs are actually the big ticket items.

http://whiteboxswitch.com/collections/10-gigabit-ethernet-sw...

$5595 for the switch, $699 for the software. You can split the 4 40G ports into 16 10G ports using splitter cables, giving a total of 64 10G ports: (5595+699)/64 = $98.34 per 10G port.

A 1M cable is $30 from here: http://www.fiberyes.com/sfp-cable-cab-10gsfp-p1m-30

So $122.34 for switch and cable.

I've never seen a 10G NIC that cheap per port.

(disclosure: I co-founded Cumulus, who is behind the software in this price comparison)

The problem for hobbyists is that they usually want to buy more like 8 ports, not 64.

Still, for simple high-bandwidth networking needs it should suffice.

Look at used infiniband gear, you will get much better support (hardware, software, cabling). Same price or lower.