This is a neat device that allows you to connect bluetooth peripherals to your ST including modern mice and joypads. Out of the box it works well with joypads, but takes a little bit of software tinkering to enable mouse support.
A quick guide on using a Gotek USB floppy emulator in your ST, conveniently store all your floppy images on a single drive and never have to worry about worn out floppy drive belts again!