On Monday, April 19, the closing of Cisco Systems' $3.3 billion acquisition of Tandberg, a Norwegian teleconferencing company, served as a product demonstration. Marthin De Beer, Cisco's (CSCO) senior vice president of emerging technologies, whose flight from San Jose, Ca., to Oslo had been canceled, and Tandberg CEO Frederik Halvorsen held a virtual press conference using the merged firms' equipment. As the ash cloud emanating from Iceland wreaked havoc on global business travel, Cisco's Telepresence service (think a very high-end Skype) boomed. Competitor Hewlett-Packard (HPQ) said that one client, a pharmaceutical firm, doubled the use of its videoconferencing service last week. Thanks to cheap and pervasive information technology, Cisco's Telepresence and its competitors have emerged as a sort of redundant network for business meetings. When face-to-face meetings are impossible, executives can go to a specially equipped conference room, flip a switch, and share bad jokes and ...