Today Verizon announced it would be crediting over 15 million customers with $90m in refunds for overcharging for data use. Most customers should see a $2-$4 refund on their bill by November, Verizon explains:

"As we reviewed customer accounts, we discovered that over the past several years approximately 15 million customers who did not have data plans were billed for data sessions on their phones that they did not initiate. These customers would normally have been billed at the standard rate of $1.99 per megabyte for any data they chose to access from their phones. The majority of the data sessions involved minor data exchanges caused by software built into their phones; others involved accessing the web, which should not have incurred charges. We have addressed these issues to avoid unintended data charges in the future."