I am toying with the idea to create an Embedded Solid State Disk. The concept is not new or complicated and if you dissect an SSD or USB Memory stick you will find two chips. One is the NAND Flash Controller and the other is the NAND Flash itself.
USB or SATA is not very available in embedded solutions so I would prefer SPI, I2C or UART as interface. The Flash Controller can be a standard MCU with the interface as a 4-6 pin expansion plug allowing a USB Memory size SSD to be connected.
A more classic solution is using a SO8 SPI based EEPROM, FRAM or Flash. They have different characteristics. FRAM is fast and have a high number of re-writes, but it small (typically 128Kb) and actually expensive. A SPI Flash can be 8Mb, but is a bit slower and have a lower number of re-writes.
If we use a decent MCU for this we could also add an intelligent search engine in SW and get the eSSD to act as a database engine capable of processing queries as well as acting as a file server.
We could easily create a eSSD that is 15 x 30mm in size with ca 10.- USD in component cost on a 8Gb “disk”. I do see other people have done similar things, so this is not a new concept. I need to think about this for a while and do some Research.