FFS may refer to any of the following:
1. When talking about computer hard drives, FFS is short for freefall sensor and is a technology found in Fujitsu hard drives that protect the drive if it were to be dropped. The technology works by moving the read/write head within the hard drive up a ramp to prevent it crashing against the magnetic medium.
2. Short for For F***'s Sake, FFS is slang commonly used in gaming and chat communications.