Every useragent going back to IE3 and NN1 support it.
I then set a cookie, and users never see the prompt again.
Cookies are sent on the first request, before auth happens.
In my extensive testing, even the most "non-techy" people are able to complete this task, while most bots fail at it.
If any bots start getting through, I can change the password.
For visitors I haven't met yet, I can give out guest credentials on the 401 page.
https://addons.mozilla.org/en-US/firefox/addon/http-auth-enh...