Now that Paypal has reached 100 million active accounts, a company executive predicts physical wallets will soon be mothballed.

“We believe that by 2015 digital currency will be accepted everywhere in the US -– from your local corner store to Walmart. We will no longer need to carry a wallet,” Paypal President Scott Thompson said in a blog post.

A new Paypal campaign challenges five residents in the San Francisco Bay Area to use only digital currency to pay for all of their purchases — no cash allowed. If it works, it could generate a lot of positive press for the company and lend credence to its president’s bold predictions.

The eBay-owned payment processor generates a sizable portion of the auction site’s net revenues and is expected to facilitate $3 billion in mobile transactions in 2011.

[Mashable]