I am building my personal private cloud. I am considering using second hand dell optiplexes as worker nodes, but they only have 1 NIC and I'd need a contraption like this for my redundant network.
Then this wish came to my mind. Theoretically, such a one box solution could be faster than gigabit too.
I plan to have 2 switches.
Of course, if a switch fails, client devices connected to the switch would drop out, but any computer connected to both switches should have link redundancy.