I've lost a micro USB Stick at EF17.
It is only about 2 centimeters long, black and has a capacity of 16 GB.
I've had some white yarn burled to it.
It contains two partitions, the smaller one holds files, you'll need to boot linux, the bigger one is encrypted.
I've called the hotel today, they told me to ask EF-staff.
My room number was 523.
I've you've found something like that, please let me know.