I had to convince my cousin I bought him a Mac, but I didn't want to support a Mac, so I tweaked KDE to look like OSX. He thought it was great how cheap he got a laptop, and was surprised Dell made Macs now. Had him fooled for about 2 years until he asked some kid to help him do something.
I just shrugged and asked him if he'd have known if he hadn't been told. Yah, cuz knows cows, not computers.