Overheard on the radio a few years ago:
"Kalamazoo approach, student pilot N1234 five miles west."
"Are you the red and blue Cessna 172?"
"Yes. How did you knnow?"
"I have color radar. N1234, go to tower 123.45."
"Kalamazoo approach, white Bonanza with black and red stripes checking in."
Approach (laughing) :
"I used to fly that 172!"