Do you love peanut butter that tends to separate the oil from the rest? Do you try to mix it back together by hand with a knife, spoon or spatula?
I found my own solution to this problem. Grab a single spiral dough hook from a hand mixer and chuck it into a power drill (corded or cordless).
Open the jar and holding it securely, turn it slowly at first so that the spiral pushes the contents downward. Once the oil is incorporating, speed up the drill and work down into the center and all around the edges (take it easy if it's a glass jar so you don't break it) to get an even mix.
Once you're done, s!ow down again and slowly raise the dough hook out, leaving only a thin layer on it to scrape (or better, lick) off.