Obviously it merely takes someone getting their hands on his USB stick to compromise security, but it does beat a Post-It under the keyboard any day.
Say what you will about suitcase computers, but at least most of them still have their keyboards with them. [danjovic] has this vintage Brazilian computer from the 1980s called a Gradiente Expert.
Regular Bluetooth 5.0 connection has a 145Hz polling rate, and connection to up to four devices by holding fn+1, 2, 3, or 4 ...