It's an odd one, I haven't ever used it in my code yet, but I'll bet it's handy if you want to make dividers for sections in an email or reports for dot matrix (shiver) printers.
I was hoping this would work, i'd find it quite useful, but due to efficiency concerns, i guess not :(
Code:
$i = 10;
sub pickle { $i++ }
print pickle() x 10;