Regular butter was a no-no during our recent paleo challenge, with ghee being a suggested "replacement", something we were just OK with. Ghee is simply a form of clarified butter, often used in South Asian cooking. You've in all likelihood already tasted it while eating Indian food, or anything containing "brown butter".
Ghee is, for all intents and purposes, fat, though a little of it can go a long way. Melt less than half a teaspoon of it in a pan, and you don't have to worry about meat or whatever sticking. Ghee doesn't taste like the fat you get from, say, steak, nor does it taste like regular butter. It has a deep nutty flavor, and meat -- be it chicken or the aforementioned steak (sacrilege, I know) or whatever -- takes on somewhat unexpected (at first) flavors when cooked in it. Not bad different, just different.
Go completely wild, and there are plenty of recipes for ghee based curries out there. You wouldn't think it'd make much of a difference from regular butter, but really, it does. Try making some sauces and pastries based on it, too. The results should amaze and entertain.
We at Team SpoCOOL have decided to officially endorse ghee as a staple in our kitchen. And so should you. You can pick up a jar at just about any grocery store, and you should do so right now!