ShortMessageService, aka SMS, is a very popular mechanism for communication between busy people.
Besides costs that are cheaper than a direct call, it also allows for store and forward messaging, so your mobile does not have to be on while message is sent. See more at http://www.webopedia.com/TERM/S/Short_Message_Service.html
SMS can be sent to foreign countries, not all service providers are equipped for this.
For some reasons some people are hooked on using SMS.
SMS BusinessValue
See for example, an article at http://www.m-indya.com/mwap/sms/user_appl.htm for various applications of this technology, including SMS chat.
Another application in Australia is for advertising where bar codes are transmitted to phones that can be used to function as discount coupons. Seen that in the business section of an Oz newspaper on 7th July05.
BusinessValue the MicrosoftWay
MS is said to have advertised email PushTechnology in WindowsMobile 2003, and implemented via the use of a ShortMessageService based intermediary. This was said to operate only on CDMA (CodeDivisionMultipleAccess) networks. But the ShowStopper is actually cost of this service, which requires the use of 2003 version of MicrosoftExchangeServer. See http://msmobiles.com/news.php/1870.html
SMS message gateways exist on the web. Anyone found good use of this outside of US? What countries and for what purposes? And why SMS ?