The theremin is a musical instrument that’s played without physical contact. A classic joke is:
 
“I’m thinking of selling my theremin. I haven’t touched it in years.”
 
“I’ve had my theremin for four months, and I’ve barely touched it!” was cited on Twitter on December 17, 2009. “I finally got rid of my Theremin… I haven’t touched it in years” was cited on Twitter on August 7, 2011.
 
     
Wikipedia: Theremin
The theremin (/ˈθɛrəmɪn/ therr-ə-min; originally known as the ætherphone/etherphone, thereminophone or termenvox/thereminvox) is an early electronic musical instrument controlled without physical contact by the thereminist (performer). It is named after the Westernized name of its Russian inventor, Léon Theremin (Термéн), who patented the device in 1928.
 
The instrument’s controlling section usually consists of two metal antennas that sense the relative position of the thereminist’s hands and control oscillators for frequency with one hand, and amplitude (volume) with the other. The electric signals from the theremin are amplified and sent to a loudspeaker.
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Operating principles
The theremin is distinguished among musical instruments in that it is played without physical contact. The thereminist stands in front of the instrument and moves his or her hands in the proximity of two metal antennas. The distance from one antenna determines frequency (pitch), and the distance from the other controls amplitude (volume). Higher notes are played by moving the hand closer to the pitch antenna. Louder notes are played by moving the hand away from the volume antenna. Most frequently, the right hand controls the pitch and the left controls the volume, although some performers reverse this arrangement.
 
Twitter
Whitney Meers
‏@whitneymeers
I’ve had my theremin for four months, and I’ve barely touched it! #halfjoking
3:59 PM - 17 Dec 2009
 
Twitter
Jack Payne
‏@iamjackpayne
From Reddit:  I finally got rid of my Theremin… I haven’t touched it in years.
10:03 PM - 7 Aug 2011
 
Twitter
Martin Norris
‏@funkedup
So I finally got rid of my Theremin…...i hadn’t touched it in years
4:08 AM - 8 Aug 2011
     
Very Viral
21 Jokes So Clever That You Probably Won’t Get Them… Definitely Won’t Get Them
PETIE ON 3 JUL, 2014
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19.) I’m thinking about selling my theremin… I haven’t touched it in years.
 
reddit
I’m thinking about selling my Theremin.
submitted October 19, 2014 by Baker359
I haven’t touched it in years.
 
reddit
I’m selling my Theremin….
submitted November 11, 2015 by Cinder2010
I haven’t touched it in years.
 
Twitter
Moe Lester
‏@Jokeboxe
I’m thinking about selling my theremin… I haven’t touched it in years.
7:11 AM - 16 Dec 2015
 
reddit
I think I’m going to sell my theremin
submitted July 19, 2016 by doonkune
I haven’t touched it in ages…