People may only just be coming round to the idea of using their fingerprints to authenticate themselves, but a PayPal executive is already looking ahead to a time when we embed and ingest devices that identify us at the point-of-sale.
In a presentation he has given at several conferences, Jonathan LeBlanc, global head of developer advocacy at PayPal, calls on industry to 'Kill All Passwords,' which he says are a broken method of authentication.
This is a view widely shared, including by PayPal, which was one of the founding members of the Fido Alliance, which counts MasterCard, Visa and many banks among its members working on standards for a biometric-based alternative to the password and username.
The most popular form of biometric authentication is the fingerprint, championed by Apple, which uses its Touch ID technology to let customers pay for goods with their iPhones.
However, in an interview with the Wall Street Journal, LeBlanc calls this type of external biometrics "antiquated," arguing that it leaves room for false positives and negatives.
In the future, he suggests, we could instead embed silicon chips with ECG sensors under our skin to monitor unique heart activity and communicate the information to "wearable computer tattoos". Another option could be an ingestible capsule that tests unique things such as glucose levels and is powered by stomach acid.
Although the ideas may seem far-fetched, LeBlanc says that PayPal is already experimenting with technology that authenticates people through their heartbeats - albeit using wearable bands rather than implants.
Royal Bank of Canada and the UK's Halifax are both working with a startup called Bionym to test the use of bracelets that authenticate user identities by analysing their unique heartbeat rhythm. Meanwhile, several banks have already moved beyond fingerprints to finger veins for authentication at ATMs.
However, PayPal stresses that it is not currently investigating some of LeBlanc's more exotic ideas, telling Finextra: "We have no plans to develop injectable or edible verification systems. It's clear that passwords as we know them will evolve and we aim to be at the forefront of those developments."
"I ground a lot of my talks in reality, but toward the end of the presentation things get a little strange," LeBlanc told the Journal.