I ran across some Solarflare 10 Gigabit cards on eBay for $12 and decided to take the Pepsi challenge. To keep things interesting they were paired with the finest $7 Finisar transceivers and a slice of Monoprice fibre. You won’t believe what happened next! Just kidding, everything worked out of the box. Linux is gonna Linux and all that. If you need a 10 Gigabit link between two systems it’s worth looking into.
NOTE: I have zero idea if these cards work with Windows, BSD, or TempleOS.
Finisar SFP+ transceiver
Solarflare SFP+ card
Monoprice OM4 LC/LC fibre
If you’re looking for a cheap 10 Gigabit switch check out the CSS326-24G-2S+RM or CRS309-1G-8S+IN.