The clients 13 are selectively connected to the host server 15 via the Internet 19 when desired to utilise a particular service using any or all of the following terminals of appliances: a GSM mobile client 13 a connected via a GSM cell site 23 and SMSC server system 25, where SMS messages 27 are transmitted between a GSM device 29 of the client, such as a mobile phone, and the SMSC server system