Partially asleep while driving and shopping

Today I was able to maintain a state of being nearly asleep while driving and then while shopping. I've done this before while driving; it helps make the time go by faster, especially when the ride is easy. (Yes, I know this can be dangerous, but I've managed to control it so far.) But today was the first time I ever maintained this state while doing something else, in this case, shopping at a WalMart somewhere here in British Columbia, Canada (either Quesnell or Williams Lake, I don't remember now).

Shopping in this state is a little bit of an adventure, but not too hard. I just try to focus on one thing at a time, and the nice thing about this state is that I generally ignore other human beings, except for the part where they're in my way, lol.

I could write more about this, but really what I'd like to do is get a machine that can measure my brain waves at times like these. I know my mental state is very different at times like this -- almost hypnagogic, but not quite -- and I'm very curious about what the brain waves will look like.