I don't know of a better option than what a number of blogs, like Daring Fireball [0] do, link the footnote number to to the footnote, end each footnote with a link back to the footnote number (typically using the ↩ character).
Kitty Giraudel wrote about a version that's a bit "extra." [1] They make a whole word or phrase the footnote link text but style automatically inserted CSS counters so only numbers have the appearance of a link. Plus, each link has a description, "Footnote," to make it more clear to screen reader users where it goes.
