For those who want a little extra security baked into their online presence.
Have been using one for awhile, very straight forward to setup with the likes of Google, LastPass, O365, etc. Compatible with Mac, Windows and any mobile with NFC.
Found the promo code online, not sure how long it is valid for - can be used for $10 USD off most of their products excluding the Security Key NFC.
Using current exchange rates, the Yubikey 5 NFC at $40 USD delivered equates to ~$51 AUD.
edit: updated the link back to the Yubikey 5 NFC instead of the 5C
edit 2: not valid for the Security Key NFC