Google Wallet is getting an update which will make it even easier to send money to pretty much anyone.
The latest version of the app will operate money transfers via text message. Once you have funds in your wallet, all you have to do is send a text with a secure link which the recipient can open and the funds will be transferred to their account almost instantly.
Previously, the service used an email address to initiate the transfer but this will be even easier for those who aren't connected by mail. You can also set it up to directly take money from your credit or debit card, pretty much meaning you'll never have an excuse for not paying back alone again!
This functionality seems to only be available in the United States right now, we'll have an update if it rolls out elsewhere.