QuickPage is a client/server software package that enables you to send messages to an alphanumeric pager. The client accepts a message from the user and forwards it to a server using SNPP. The server uses a modem to transmit the message to the recipient's paging service using the TAP protocol (also known as the IXO protocol).
mail2sms converts a (MIME) mail to a short message, allowing search/replace, conditional rules, date/time dependent actions, customizing the output format, etc. The output defaults to 160 characters, which is perfectly suitable for sending the text to a GSM telephone as an SMS message. This software does not include any code for actually sending the text to anything else but another program or stdout.
email2sms is a filter written in Perl which converts an e-mail into a form suitable for sending as an SMS message. Its main advantage over the alternatives is that it uses the CPAN module Lingua::EN::Squeeze to compress the text down to as little as 40% of its original size, so you can get much more of your e-mail into the 160 character limit imposed by SMS. It is fully MIME compatible, and has many configurable options, including removal of quoted text. Ideal for use with procmail. A Perl script for sending the output to a typical e-mail to SMS web gateway is included.
SMSLink implements a client/server gateway to the SMS protocol. It requires the use of dedicated hardware though (a serial GSM module). Both SMS emission and reception are supported. The server only runs under Linux at the present time and also supports interactive mode via telnet. The command-line client already exists for Linux, Solaris and HP-UX. A basic web interface is provided. A Win32 client is in the works.
nmsms is a very simple program to announce incoming email to an SMS address (email address) defined at compile time. The original From: and Subject: header are included in each mail announced.