in reply to opinion - enormous input files
sort file | uniq -c
perl -e 'print `sort file | uniq -c`'
Once (shame on you!)
Twice (shame on me!)
More often than I'd like to be
All the time
Just when answering stupid polls
Who you callin' a fool?
I refuse to vote in this ridiculous poll
Results (503 votes). Check out past polls.