I love night trains. I’ve taken them from Warsaw to Prague, Prague to Zurich, and Verona to Paris. It’s by far my preferred option - you get a decent nights sleep and whilst the tickets are more expensive it’s one fewer nights in a hotel which normally offsets it. I still really want to do the two in the UK, the Caledonian Sleeper and the Night Riviera.
Would love to take these more often if there were more (any) west to central Europe connections! (perfect routes for it too, since the flights are long and the infrastructure is less high speed)
A car+sleep train would be amazing to bring back, too.