I find it common in my writing to end up a sentence with a footnote reference mark. Should the footnote mark come before the stop or after it?
... this is some text1.
... this is some text.1
Noldorin and SabreWolfy have logical answers, but in the world of typesetting, logic is not respected. At least in the field of scientific publishing, where footnotes and references are common, publishers tend to have very strict guidelines about where they want the marks. In that case, you're not really free to choose yourself. For example, most of the physics and chemistry journals want references after punctuation:
as first demonstrated by Smith.1
As a consequence, in these fields, people mostly tend to follow this usage, even in works for which there is no restriction imposed.
So, what I'm saying is: if you're free to do what you want, go ahead, but check the relevant style guide first.