The Sony CFS-C7 from 1982 is a bizarre drum and chord machine, with a built in tape deck for good measure. It's been covered by TechMoan, who has featured in our news items numerous times with his unique electronic finds. Having received it as untested, he diagnoses and fixes a number of issues with it, as well as pointing out some of the IC's on the sound generation elements.
As mentioned, it has a drum machine built-in which doesn't appear to enjoy being near wifi - though the resulting effect it produces sounds good to me! The chord section works very much like an electronic organ accompaniment, playing arpeggios or held chords to the rhythm. If only Simon the Magpie could get his hands on one of these.
Casio KX-101 is another bizarre combination of keyboard and boombox which has been covered by the 8-Bit Guy:
With Delta CEP A and friends
New Stereo features and FX algos
A detailed look at the new Wavetable synth
Matths gives it a workout