Square Cash is Square’s shot in the crowded peer-to-peer payments space. An interesting exercise in minimalism, Cash takes no app and hardly any interface. Instead, it piggybacks on your email client. Send money by email to friends by CCing and putting a dollar amount in the subject line. Once both of you have linked your debit card to the service, payments are automatic. For some banks, even instant.

I’m super interested to see how this experiment works out, especially with a polished and aggressively marketed alternative. In fact, I’m so interested I made a video about it!