The Superbrain-II, from Intertec Data Systems.
I bought it in 1981.
I paid around 10 grand (in Dutch Guilders)
I must have been totally out of my mind I guess..
But it gave me a lot of experience with computersystems and software.
IThe SuperBrain was a dual Z80 cpu machine (one Z80 cpu for disk-I/O, and the other Z80 cpu for the OS)
I was making databases using DBASE II (Ashton Tate) for my dads company using this machine.
Powerful machine for that time.
The two red keys (left and right) of the main keyboard had to be pressed simultaneous for a reboot.
The silly thing in the design was, that the floppies were ALWAYS running.
I modified it, and that was a good thing.
There was even a magazine for the Superbrain (bimonthly: SuperLetter), and I wrote several articles for it.
I had even changed the BIOS Eprom, and installed SUPERbios.
Check it out, in a YouTube video: