I used to travel by ferry regularly. I grew up on an island where the only way to mainland was by ferry. That changed when I was just in my teens, as a 14 km bridge was built which render the ferry useless. There is still a ferry on the other side of the island, but it's more of a tourist attraction now instead of a working transport.
Yes, a couple of times. I remember once, as a child, a girl slipped on deck. She wasn't hurt, so it was hilarious. A ferry memory I'll always carry with me, lol. Sorry girl who slipped on deck, but if it was me, you would've laughed too.
Many times, Circular Quay to Manly & return.
Once on Hydrofoil.
On 'little' ferry Circular Quay to Luna Park, & return, a few times.
Across Nile River to 'Valley of the Kings'.
Down, as well as across, my city's river, by 'little' ferry & 'big' ferry.
Vancouver City to Victoria Island & return.
Trip on Q River in Seville.
I dislike ferries. I get motion sick just standing on a pontoon. Even crossing to Manly I hate. I make sure I know where my life jacket is and try not to look at the water. When taking our hire car across from Spain to Portugal we all got out of our cars and I decided I had to have a toilet break. After going downstairs and finding the smelly toilet I was ubable to go. Apart from the stench, the toilet was a hole made in the bottom of the ferry which you were supposed to stand over. Shock! Horror! I was concerned tye ferry would lurch at any tine and I would disappear through the hole. Added to that I was wearing culottes so had no option to hold on until we reached Portugal where my husband had to try to explain to the guards that I urgently needed to wee.
Best one was Seattle to Vancouver - scenery was amazing! We have a little local ferry which crosses the Brisbane River from Bellbowrie, Queensland to Ipswich. Only on ferry for a couple of minutes but again the view down the river is beautiful. Have done several others in various countries but the Vancouver ferry beats all.