Most (not all, but most) of the big ferries I have been on have been off the coast of Newfoundland. Loved them! The other one, which took even longer, was the ferry from Sweden to Poland (Gdansk), in 1986, and that was even cooler. Though Poland was so weird and intense in the two days I was there that I splurged on the way back to Swedish capitalism and booked an actual room -- which was wonderful. I'd just sat on the deck overnight with everyone else on the way TO Poland.