Personally, I've got some theories of my sixth sense.
I usually know the EXACT time. When I microwave something, and than I sit down in a sofa 10 seconds away or so, I always get this "Now it's time to get up and check" feeling when it's 15 seconds away from being done.
And no, I never count the exact time on my watch or any watch for that matter.... I just "know".
Never.
I also have a habit of looking at my clock when it JUST hits a clear number. Like 8:00 point sharp for example.
I also know when the time of 13:37 happens. I always happen to look at the clock when that time strikes. It's kind of weird...
But I believe that's my sixth sense. But surely there are scientists with PhD's and their theories to prove me that there's nothing special in knowing the exact time, all the time.