Kermit the Frog's eyeballs were originally made of these light sports balls
[DOC] [TLE] Muppets on display at the Smithsonian | Deseret News [PAR] Jul 14, 2008 ... U.S. & World  Sports ... Kermit the Frog greets visitors near the entrance of the 
International ... Muppets under special lighting, behind glass and closely guarded
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