My supervisor at work calling the PC "CPU".
I had a teacher last year and she was talking about computers, I told her that I build one and then she told me that she always buys new computers on ebay, and she tells her husband to upgrade the RAM, I asked her "why?" and she said "to make the computer faster, and when I can't add more RAM I just sell it and buy a better one." What a waste of money, I didn't explained her that RAM doesn't make a PC faster by adding more, because I'm sure she was going to ignore me anyway. She just uses the PC for browsing and using Microsoft Office.