Money transfer just got even more ridiculously simple. If you thought internet banking was easy, or PayPal was nifty, get ready to be mind-blown by Square Cash. Forget user IDs and pin numbers and ATM machines… or annoying security gadgets from the bank. All you need now is email. Yes, send your friend money via email–simply send them an email with the amount you wish to transfer in the subject line and Cc: firstname.lastname@example.org. You will receive a reply from Square prompting you to link your debit card. Your friend will also be prompted to do the same and voila! Your cash transfer is completed in 1-2 business days. This service is now free, only capped at $2500 per week for senders. Square Cash is currently available in the U.S. only but they may soon take over the world. Watch out for the upcoming iOS and Android apps, or start using it now.