It's actually called the Interac e-mail money transfer service, and they use a thing called suspense accounting. So when one bank consumer pays at his bank, the other bank floats that suspense account and puts the money into the other person's account when he receives the money.
So it looks instantaneous in real time, but from the way I understand the way it was set up, there's still an overnight batch process that actually does all the reconciliation. They just set up suspense accounts. The other unfortunate part is that they created this new system, but then they put in all these restrictions, and it's not really a viable product.