Instant Messaging--Another Format to Worry About?  

IM lived for years as an obscure technology in the shadow of the WAP (wireless application protocol) wireless Web, and is still used chiefly by teenagers. But IM has recently become a source of revenue for financially beleaguered telecoms, and has been discussed as a possible replacement for e-mail.

Perlin, Neil E. Intercom (2003). Articles>Writing>Online>Instant Messaging