Earlier quoted context omitted.
Similar to the Theremin is the ondes Martenot. Jonny Greenwood (Radiohead) describes it as a "very accurate Theremin". You can hear it particularly on "Where I End and You Begin" from Hail to the Thief. Ed O'Brien compliments its sound using an EBow (back before he had the sustainer) in that song. https://en.wikipedia.org/wiki/Ondes_Martenot
Yes! I always think first of How to Disappear Completely, which I think was the first song he used it on. I remember watching some concert in college from the Kid A days, and he would have like 3 Ondes Martenot players on stage with them, crazy stuff from the band that wrote Creep like 5 years earlier. https://www.youtube.com/watch?v=cvWwMhRsRgo
https://www.youtube.com/watch?v=UlhaJqqIfCE
This is also cool; live version of How to Disappear Completely at the start and one of the few Jonny interviews where he speaks. From a documentary on the Ondes Martinot.