Blimey, and I thought Brittany ferries was expensive.
IIRC, my first Plymouth-Roscoff return as foot passenger (1995) was about £24, and I was outraged when they doubled the price a couple of years later. I can't remember what I paid for Poole-St Malo with a bike in August 2012, with cabin, but I'm sure it was under £100, as I'm a tightwad. I think the bike was probably free, but not sure.