Strom, I assume you have tried all the usual commercial athletes foot stuff.
Exposure to sunlight is reputed to cure some cases . . . and going barefoot outdoors can't hurt hammertoe or mallettoe . . .
Earthclinic.com often has remedies that are surprisingly helpful for common ailments, and the system of voting yea or nay and leaving comments is useful.
That site has a lot of apple cider vinegar adherents who claim a high rate of success in treating athlete's foot.
Smaller in number, there is an "earthy" group of enthusiasts on the earthclinic site who insist that soaking their feet in their own urine cured their athlete's foot when nothing else worked. Hmmm. About as cheap as sunlight. Let us know how it works.
This supposed aversion of athlete's foot fungus to host urine undoubtedly has evolutionary roots as does almost everything else that we deal with in the Primal world. Here is a theory. Hosts dumb and clumsy enough to urinate on their feet are probably considered by smart fungus to be poor long term prospects for fungus habitat, leading the fungus to seek longer lived hosts. But we crafty primal types can fool the fungus into thinking that we are dumb enough to urinate on our feet by just soaking our feet in our urine, achieving the same net result of a fungus exodus, but without shedding the IQ power that brought us to the Primal site in the first place.