When working in the Best Buy PC sales department (about 4.5 years ago) we'd get all sorts of characters in there. Due to our location, we either got the ghetto factor or the redneck farm factor. If anyone knows the northwest side of Dayton, OH you know what I'm talking about.
One customer in particular still sticks out. This was when Intel still had 95% of the market share and AMD was still pretty rare, especially at a Best Buy. The guy approached me and asked for a "Pelentrium" (or some other variation of Pentium) computer in his best ghetto dialect. When I asked him if he meant Pentium, he strongly demanded to see his mispronounced computers. I informed him that we carried no such brand, but we did have Pentium computers. At that point, he told me I was baiting and switching, he knew exactly what he wanted, and was going to go get it at Circuit City, across the street.
Another good one was the elderly folks that decided they didn't need some of the files in thier windows folder, then couldn't figure out why the computer stopped working. Since Best Buy doesn't support any software issues (not covered under warranty or service plan) they were pretty much screwed, but we helped em out and restored their system, then strongly encouraged them to invest in some "Learn Win98" books.
Ahhh, the good ol days of dealing with the unwashed masses