I collected a few old network cards and installed them in an old computer with reasonable power draw.
It turned out rather painless to set up an OpenBSD/pf firewall. I am currently adding rules and testing. One of the network cards seems to malfunction, one danger with random hardware.
Extra interfaces allow more finely grained policies.
It might not be possible to get all the things you want, but perhaps it is possible to get the most important. This appears to have happened, and with some luck, it may well continue. What can I do to help it along? Be good, for goodness sake.
If am well slept, get some light and have a reason to get up, I am sure to. This is far from becoming a habit, I am fighting the alarm clock, but the code is cracked. Remember it is a cycle.