#!perl -l ($}=$}%1e9*$_)=~s~0+$~~for++$}..pop;print$}%10
Improving my tie-breaker by a massive 0.00058 strokes. Call it professional pride.
#!perl -l ($}=$}%9e9*$_)=~s~0+$~~for++$}..pop;print$}%10