If people dont fancy driving down to calais, you can now get train from any london southern eastern railway stations to dover priory and then get the ferry to calais.(p and o ferry is included in the price). This offer applies to peak times too and railcard also accepted during peak times. This also can be used to get the newer fast trains from st pancras to dover priory which would cut journey times by half. this deal is poorly advertised but it definetely works.