Former CFNY deejay Pete Fowler has a radio show entitled The Lost Indie City and he sells tee shirts with a big yellow 45 rpm adapter on it to promote the program. I've got one, and wear it often.
It's a fantastic conversation piece. It never fails that when I go for a walk wearing this shirt some guy, usually in his 50s or 60s, will light up and tell me he remembers those. I myself used to buy 45 singles at my local Sam the Record Man so I always had such an adapter on hand.