The Travelski Express is the Eurostar Ski Train to the Tarentaise, but privately chartered by tour operator Travelski. Tickets are only available as part of a Travelski package.
Eurostar's direct overnight Ski Train to the Tarentaise region of the French Alps and has a cafe bar and reclining seats, but no actual couchette beds.
Travelling to Swiss resorts takes a little longer than to French ones, but it's a scenic journey and most resorts have a train station right in the village
Combine a Eurostar, ICE and the Alpen Express sleeper train, and you can travel overnight in comfort to a wide range of Austrian ski resorts, and get two extra days on the slopes.