I have a few times but the finniest was when my husband, at the time, had a Mercedes which I did not want to buy for us, and for some reason I was down south in the Margaret River wine region with a girlfriend, in his car (I had my own also).
To my horror it broke down!
The people in the local garage were sniggering at us, and we ended up having to get a tow truck.
There is probably another time I have used one, however this one stands out.