I flew into London for a work thing and wanted to hop over to Dublin for the weekend. Instead of booking a last minute flight, I took the overnight ferry from Holyhead to Dublin for about $15 with a student discount I did not even know still applied. The trick is checking ferry companies directly instead of aggregator sites, they often have off peak deals that do not show up on search engines. I slept in a recliner chair, woke up in Dublin, and saved close to $185 for about 4 extra hours of travel time. Has anyone else found a ferry route that beats flying when you factor in airport transfer costs?