This won't capture multiple maximum values, but:

hash.invert[hash.values.max]

I'd be interested to see a benchmark profile of the suggestions.

On Thu, Sep 9, 2010 at 4:37 PM, Brian Candler <b.candler / pobox.com> wrote:
> hash.sort_by { |k,v| v }[-1][0]
> --
> Posted via http://www.ruby-forum.com/.
>
>