I use it between the house and shed to get network into the shed. By using a couple of $50 surplus Cisco switches, some aftermarket SFPs, etc I have the internet in the shed, the home network in the shed, geographic isolation for my backup drive, and similar features. I converted an old ADSL modem into a wirelss bridge, and have wifi in the shed as well, but only for internet (none of my private networks are ever put on wifi) - If i choose to, I can even run PoE phones in the same setup, across the existing fibre.

Some of this was done for keeping my skills current, there is Cat5e in the joint use trench alongside the fibre, but there is also 16mm2 3 phase cable in the same trench, and given I can pull over 85A per phase, the fibre is better for noise reduction. The Cat5e were tested as "OK" but I use them for alarm cables rather than network.