Riddles from the Border Regions, 11/19/11

First I'm emptied
Then I'm filled
Bobbing
Till my words are spilled.

This is a riddle about a message in a bottle.   So the bottle is emptied -- glug, glug, glug -- then a note is written.   Perhaps it's a hasty note of desperation.   Perhaps it's the outpouring of the longings of the human heart.   Then the bottle is sealed and entrusted to the vast oceanic messenger boy.   We heard some good alternative answers, too, like the bobbing of a fountain pen as the words spill forth on the page.  Or the helty load of words in a newspaper or postal carrier's bag.

NEW RIDDLE:
Despite their name
Boats of this kind
Need not be
Side by side by side.
(answer:  see 11/19/11)