This is an Amstrad PPC640, an early laptop first produced by Amstrad in 1988. The PPC stands for Portable Personal Computer, while the 640 indicates the amount of RAM the machine has; 640 KiB.
The PPC640 succeeds the PPC512, which was almost identical but came with 512 KiB of RAM.
The PPC640 features a built-in modem which seems to be working, but I don’t have access to a land-line to test it with at the moment. The two 3.5″ floppy disk drives are both functional and can read and write to 720k formatted disks.
I picked up this PC with a bootdisk containing MS DOS 3.3. Because 3.5″ floppy disks haven’t quite reached total obsolescence yet, it’s relatively easy to create a new boostdisk. See the links below.
The screen is an LCD which isn’t back-lit, so viewing can be a bit tricky in dimly-lit areas and from certain angles.
The PPC640 runs MS DOS 3.3 and has the potential to run software targeted at that version of DOS. So far I’ve had luck with a few games from dosgames.com.