I've got an SP3 I5 256.
No, I don't have anything plugged in, but I did note all those Toshiba products when I searched for it!
Since I did a clean reinstall last week I'm pretty sure that the only storage I've attached at all was a (Sandisk) microSD card -which is now out.
I could see a sort of logic if it were related to say storing app data on microSD, but I've checked and inserting other USB sticks doesn't trigger extra entries.
Screenshot of the settings page attached - does nobody else have anything under the Trusted Devices (Xbox etc) area in here?