I remember a friend had one of these in highschool, which I never used but thought it was the coolest-
..in 1983 I bought my first one of these
And remember lusting over this in college, which is what I really wanted, but was out of my grasp at the time-
after continued bad luck with those I went on to one of these in 1984
Instead, I had a cheap recording Walkman type deck with FM radio (not Sony, but can't remember the make) that I'd carry around and use as my car radio/tape player. I got a second one and soldered up a cable that let me go off to the park with my guitar and record a track, then play it back while overdubbing another part to the other Walkman. Horrible tape noise and sonics, especially after a couple bounces, but doing that out of a book bag in the park was pretty sweet.
..I also used to put the mic inside a pair of Koss headphones and record my albums that way because I had no jacks on my stereo
Before I got a hold of the cheap dynamic mics to use with my dad's R2R I'd use an old pair of Koss or Sony headphones as microphones.
In 1986 I bought a used Yamaha MT44D four track cassette / mixer which I still have in a closet with a valise full of old college era 4-track project tapes-
and mixied them down to a Yamaha K720 cassette deck which I bought new while working at a stereo shop and dearly loved. Great machine. Many, many hours of refining perfect mix-tape song order transitions were spent with that one.