Nabu PC
Nabu PC is a computer released in 1982 in Canada. It can boot exclusively from a network via the "ADAPTOR" port.
There is also a version for developers with a floppy disk drive. We don't know if the public version can boot from this drive without firmware hack.
The PC is called "HCC": Home Cable Computer.
It runs on a 3.58MHz Z80A, has a TMS9918A VDP and the AY-3-8910 PSG. It has 64kB RAM. So, this makes it almost an MSX1.