In an otherwise unremarkable interview with its inventor, I learned that Lenin played the Theremin:

I brought my apparatus and set it up in his large office in the Kremlin. He was not yet there because he was in a meeting. I waited with Fotiva, his secretary, who was a good pianist, a graduate of the conservatory. She said that a little piano would be brought into the office, and that she would accompany me on the music that I would play. So we prepared, and about an hour and a half later Vladimir Il’yich Lenin came with those people with whom he had been in conference in the Kremlin. He was very gracious; I was very pleased to meet him, and then I showed him the signaling system of my instrument, which I played by moving my hands in the air, and which was called at that time the thereminvox. I played a piece [of music].

After I played the piece they applauded, including Vladimir Il’yich [Lenin], who had been watching very attentively during my playing. I played Glinka’s “Skylark”, which he loved very much, and Vladimir Il’yich said, after all this applause, that I should show him, and he would try himself to play it. He stood up, moved to the instrument, stretched his hands out, left and right: right to the pitch and left to the volume. I took his hands from behind and helped him. He started to play “Skylark”. He had a very good ear, and he felt where to move his hands to get the sound: to lower them or to raise them. In the middle of this piece I thought that he could himself, independently, move his hands. So I took my hands off of his, and he completed the whole thing independently, by himself, with great success and with great applause following. He was very happy that he could play on this instrument all by himself.