Ok, this didn't happen to me, but could've.
Two days ago I was driving and happened to look at the temperature gage on the dash, and I could see the needled swaying back and forth, not getting to the red section, but definitely higher that it usually goes. I got to work and let the car cool down, and then popped the hood.
I see the reservoir that the anti-freeze/coolant goes in is empty. I knew that wasn't good. So I got a jug of coolant and put it in. I noticed the engine had white splotches all over it, so it was obivousg there was a leak somewhere.
I got to work today and decided to open the hood and see if I could find any traces of the leak. After I got the hood open I hear 'sssssssssssssssss' and look around. Then, on the top of the radiator, I can see a long thin crack.
I dropped the car off at the shop, and walk to my parents place to see if my dad or brother can drive me to a rental place for another car. I find out that dad is off his feet for 4 weeks, he dropped a weight on his foot, breaking his toe. Since he can't use his car, I'm borrowing it until mine is done.