Join me, while I disassemble a 100BASE-ZX SFP module (1550nm, 80km)
Surprisingly, these appear to be quite happy running at 1Gbit/s over ~3m of fiber! The reported Rx power doesn't even saturate for the FS.com modules (though it does for the Startech module)
Oh: sorry for the bad photos... I wanted to share, but also couldn't be bothered to get the better camera (and my phone camera is terrible).