You can quite easily make all USB devices on a machine ReadOnly by adding a key to registry, it is quite easy and painless.

Once the registry key is added and set you may have to wait a bit or eject and reinsert the device but then the device is ReadOnly.  ‘Unlocking’ the drive again is equally easy, you just set the key value to “0” (zero) and everything is back to normal..

Maybe even an ide for a prank on some of your friends 😉

Key to create;
Value DWORD; “1” = ReadOnly, “0” = Normal mode.