Alpina's compact mechanical calculator

The good-looking Alpina “competitor to the Curta” from 1961 is seen briefly in this video:

Edit: oh, here’s a video of the machine in action:

There’s a better photo at the Science Museum.

And more detail, and a very nice photo, in this forum post, which tells us there was a short second production run in 1971:

See also

The video is about the TI SR60A, a programmable desktop calculator from 1977 (and an HP-67 is also briefly seen):