Our founder Alex had his first xNT RFID implant put in a few years ago sourced from Amal at Dangerous Things. That worked really well to enable him to open all the doors at DoES Liverpool where we keep our office. it also allows a small amount of data to be stored in it and retrieved but that’s about all it can do. Alex wanted to go a bit further and a couple of years ago had his first true multipurpose computer chip implanted, the Apex Flex also from Dangerous Things. This allows him to develop and source applications which he can then download into the chip in his hand via his mobile phone. There are a limited number of apps available written in JavaCard OS but they are really useful. Some store SSH/PGP keys so he can log into his laptop securely, authenticate to websites and sign emails and code. Other apps do the generation of HOTP and TOTP keys (what you use the Auth apps on your phone for when you log into websites).
Here is a little video demonstrating what he can do by downloading an application to it which allows him to wave his hand and open a website on a mobile device!