This has been nagging at me in the back of my mind for a very long time. Way back in 5th grade grammar class we learned a term that referred to how people often make grammatical errors because they are trying too hard to sound grammatically correct, but they don't really understand the rules.
Examples are:

"Just between you and I..."
"If you have any questions, send Joe or myself and e-mail."

I think it starts with "hyper" or "super", or something like that. Please, can anyone tell me what the word is?