EuroCity International
EuroCity (EC) is the brand name used to designate European best daytime international expresses. A modest supplement is usually payable in addition to the fare, which includes the seat reservation fee. The type of rolling stock varies: some EuroCity trains are operated by TGVs, others by German ICEs, others by Spanish Talgo trains, and others with conventional locomotive and coaches.

InterCity
InterCity (IC) is a brand name used by a number of countries (Austria, Belgium, Germany, Hungary, Italy, Netherlands, Switzerland) to designate the best internal express trains. Supplements are not charged in Austria, Belgium, Netherlands or Switzerland, but a small supplement (a few Euros, not much) is payable in Germany , Italy and elsewhere.

Thalys International http://www.thalys.com
Thalys is the brand name for high speed trains (basically French TGVs) running between Paris , Brussels, and Amsterdam or Cologne. Advance reservation obligatory.

Eurostar International
High speed train service from London to Paris and Brussels via the Channel Tunnel. Advance reservation is obligatory.

Eurostar Italy http://www.eurostar.com
Not to be confused with the London-Paris Eurostar, Eurostar Italia is the brand name for Italian high speed trains linking key Italian cities. Some Eurostars are designed to run on special high speed lines, others can run faster than normal trains on conventional line. Advance reservation obligatory.

Cisalpino International http://cisalpino.com
Fast trains (a type called "Pendolinos") linking Milan with destinations in Switzerland, and with Stuttgart.

TGV France http://www.tgv.com , http://www.lyria.biz
TGV (Train à Grande Vitesse) is the French high speed train. TGVs link all parts of France, and Paris with Geneva, Lausanne and Milan. Advance reservation is obligatory.

ICE Germany
ICE (InterCity Express) is the German high speed train. Operates all over Germany, and on international EuroCity services from Germany to Amsterdam, Vienna, and Switzerland.

Dutch Flyer http:// www.dutchflyer.co.uk
The dutchflyer was formerly known as the Amsterdam Express. London to Amsterdam rail-sea-rail service.

X2000 Sweden
Swedish fast train, linking Swedish cities as well as Stockholm and Gothenburg with Copenhagen and Oslo.

AVE Spain
AVE (Alta Velocidad Española) is the Spanish high speed train, based on the French TGV. Links Madrid with Barcelona, Cordoba and Seville. Advance reservation is obligatory.

Talgo Spain http://www.talgo.com/htm/recorridos1.htm
Some are fitted out as overnight hotel trains, others as premier daytime trains. Talgo 200 trains run over the nigh speed line between Cordoba and Madrid. Altaria trains use the latest and most modern Talgo coaches. Seat reservation is obligatory.

Altaria Spain
Brand name for premier daytime services between Madrid and Alicante, Madrid and Barcelona . Altaria trains use the latest type of modern Talgo coaches.

EuroMed Spain
Brand name for high speed TGV derived trains running from Barcelona to Valencia and Alicante.

Alaris Spain http://www.renfe.es/glineas/trenes/alaris.html
Brand name for high speed trains running from Madrid to Valencia.

Arco Spain
Brand name for quality trains, but slower than EuroMed, linking Barcelona and Valencia.

Alfa Portugal
Premier trains between Lisbon and Oporto.

They can be divided into three groups: sleeping trains, couchettes and reclining seats.

European sleeping-cars provide compact, carpeted bedrooms with proper beds and a washbasin, and towels and toiletries are supplied. For the daytime parts of a journey, rooms normally convert into a sitting room with sofa and small table.
The genders are segregated in a sleeper, unless all the berths in a compartment are booked by people travelling together. A woman travelling alone will be booked into a compartment reserved for ladies only. A man and a woman travelling together but choosing to travel by 3-berth sleeper will be booked into two different 3-berth rooms, one for male passengers and one for female passengers.

Couchettes offer basic, inexpensive sleeping accommodation. By day, a couchette compartment is an ordinary seating compartment, with three-a-side bench seats facing each other (the picture of the French couchette below shows the middle bunk lowered to form the seat back in daytime mode). At night, the attendant will convert the compartment into a sleeping compartment by folding bunks out from the wall. A pillow, sheet and blanket are supplied, and each berth has its own reading light. Washrooms and toilets are available at the end of the corridor.
Although the genders are not normally segregated in couchettes (you do not normally fully undressed), on certain routes it is now possible for women to ask for a berth in a ladies-only compartment.

The reclinig seats are the cheapest option to night travel. In some cases it will be necessary to use one of the previous options. In other cases it will be enough with a seat booking or even this could be the only option. Of course that this is the most uncomfortable among night options, but normally they don't require any supplement.

EuroNight International
EuroNight is the brand name used to designate Europe 's best international overnight expresses. All cars are air-conditioned, and comfortable sleeping accommodations will be available.

Elipsos http://www.elipsos.com
Overnight trainhotels between France and Spain, Switzerland and Spain, Italy and Spain.

CityNightLine International www.CityNightLine.ch
A company running international hotel trains overnight from Berlin-Zurich, Dortmund-Vienna, Hamburg - Zurich, Dortmund-Cologne. Special fares apply, ordinary rail tickets are not valid but there are big discounts for railpass holders. Sleepers, couchettes and reclining seats are available.

Berlin Night Express http://www.berlin-night-express.com
Berlin Night Express links over night Scandinavia with the German capital Berlin trough the Baltic sea. Instead of paying extra for accommodation you can use the night train as a combined hotel and carrier.

Estrella Spain
Quality overnight train, air-conditioned with seats, couchettes and sleeping-cars. There is no supplement for travel in a seat, only the normal supplement for couchettes and sleepers.

Connex Sweden http://www.connex.info
Private company operating long-distance night trains through Sweden e.g. Stockholm to Narvik.

Circumvesuviana http:// www.vesuviana.it
Times and fares for the railway linking Naples, Pompeii and Sorrento, in Italy.

FEVE http://www.feve.com
Local trains Bilbao-Santander-Oviedo-Ferrol.

Euskotren http://www.euskotren.es
Local trains Basque Country.

Rhatische Bahn http://www.rhb.ch , http://www.glacierexpress.ch
Operator of famous Glacier Express through Zermatt - Brig - St Moritz.

BLS Bern http://www.bls.ch
Bern-Brig private railway.

http://www.goldenpass.ch
Private railways through Zurich, Luzern, Interlaken, Montreux, Geneva.

Scottish Steam Train http://www.steamtrain.info
From Fort William to Mallaig. Simply one of the great railway journeys of the world.

Raumabanen Railway http://www.raumabanen.com
One of the most spectacular steam trains in Norway.

Flåm Railway http://www.flaamsbana.no
One the most beautiful railway lines in the world.

TransSiberian http://www.waytorussia.net/TransSiberian/Intro.html
It is the world's longest single-service railway, take a trip between Moscow and Vladivostok.

The Alandalus Express http://www.alandalusexpreso.com
It is a luxurious moving hotel, a unique lookout point to contemplate the Spanish Andalusian scenery.

The Orient Express http://www.orient-express.com
One of the world's most celebrated train, carries passengers across Europe in the style of a bygone era.

http://www.trenes-de-lujo.com
Touristic routes in luxury trains worldwide.

Arlanda Express http://www.arlandaexpress.com
It links Stockholm to the airport.

London airports expresses
http://www.heathrowexpress.com
http://www.stanstedexpress.com
http://www.gatwickexpress.com

http://www.eurorailways.com/brochure/index.htm, where you have several pdf brochures explaining individually many of these special trains.

http://www.europeanrailguide.com/european_trains.html

http://www.seat61.com

You may visit our forums to pose your doubts as well.