The Gotek drive (with a FlashFloppy or HxC firmware) has a special direct access mode that allows it to be used as a poor's man hard drive, offering access to up to 32 GB of storage space. It is accessible via the track 255. [https://hxc2001.com/download/floppy_drive_emulator/SDCard_HxC_Floppy_Emulator_Direct_Access_mode.pdf Source]
This is a great feature as it alleviates the need for another mass storage expansion. And the relative slowness of this solution compared to a proper mass storage device is not much of an issue on , as the FDC is quite fast for the Amstrad CPC.
This special Gotek direct access mode is supported in [[SymbOS]]. [https://www.cpcwiki.eu/forum/applications/symbos-with-hxc-direct-access-fat32-support/ Source]