[d3ad0ne] came up with a way of dumping files onto an SD card by using the USB HID protocol. We’ve seen this sort of thing before where a microcontroller carries an executable to extract data.

This feature isn’t exclusive to the Leonoardo, as [Michael] explains in a build he sent in – the lowly Arduino Uno can also serve as a USB HID keyboard with just a firmware update.

Additional info The HID Omnikey 5325 CL USB Prox is a high-performance, USB smart card reader for desktop use that can be used with any HID proximity card. It is complete with a convenient card ...

Integrates seamlessly with the contact interface of any HID Crescendo™ card. USB smart card reader with biometric verification capability for desktop use. Especially well-suited for logical access ...