Accountability score: 66.3
2006 rank: 1
Global 500 rank: 95
Vodafone, Europe's largest cellular provider, tumbled a bit from last year, when it was No. 1. But it is still the highest-ranked telecom or tech company on the list. Vodafone has worked with the World Bank to develop strategies to use mobile phones to expand access to financial markets in developing countries. In Africa, for example, consumers can use the M-PESA network to check their bank accounts and make deposits and withdrawals via cell phone. In the U.K., a new test program uses text messages to remind diabetics to take insulin and offer confidential health advice to teens. 
