Mark O’Neill has a nice article on how to get notified by SMS when someone contacts you on Pidigin.
There is a plug-in available for Pidgin called gSMS which will notify you by mobile phone SMS when someone tries to contact you by Pidgin and you don’t respond within a specified time frame. This would be useful if you had to step away from your desk but you were expecting an important message. By configuring this plug-in, you can be told by SMS that the person left a message and you can get back in touch with them as soon as possible.
Pidgin is an instant messaging program for Windows, Linux, BSD, and other Unixes. You can talk to your friends using AIM, ICQ, Jabber/XMPP, MSN Messenger, Yahoo!, Bonjour, Gadu-Gadu, IRC, Novell GroupWise Messenger, QQ, Lotus Sametime, SILC, SIMPLE, MySpaceIM, and Zephyr.