Besides its 128 MB of Flash ROM, The!Cart has a built-in 512 KB RAM chip. This chip was required because the physical bank size of the Flash chip is 64 KB, i.e. only full 64 KB blocks can be erased. So without the built-in RAM, a standard Atari 48 KB or 64 KB computer would not have been able to update The!Cart. Using the built-in RAM of The!Cart for other purposes has always been somewhere on the very long to-do list, but time did not allow me to pursue that aim.
Luckily, in 2019, my fellow Atarian Holger Janz received his The!Cart and found the idea of writing a RAM disk driver for it encouraging. He likes to use real hardware and real programming cartridges, and we all know that having a RAM disk there is a very useful thing. He first went into the details of DOS 2.5 and the existing RAM disk implementation for it and after some weeks he released it to the public. Support for other DOS versions is planned.
The video below shows how The!RamDisk can be used. The detailed documentation of The!RamDisk including ready-to-use disk images, source code, and test programs are available at https://github.com/HolgerJanz. You can follow the development, ask questions and give feedback via the A.B.B.U.C. thread (German) or the AtariAge thread (English).