Fat fingers and/or long nails aren't the best thing for working with touch screens. I don't often need to sketch something on my iPad, but when I do, using a finger is just plain awkward. I tried some of the cheapies from Amazon, but they were horrible. They were fine for tapping on the keyboard, but not for drawing. Terry found the Pogo Sketch Stylus, and while it was better, I still wasn't sold on it. It has a capacitive foam tip that I always worry about damaging, or worse, having it pick up something that could scratch the screen.
I recently heard about a new stylus called the iFaraday, and decided to give it a try. It's the same length as the Pogo, but a bit bigger around, which makes it more comfortable to hold. The tip is foam, covered in a slick metallic fabric that glides across the screen like butter. It works equally well with my iPad (bare screen) and my new iPod touch that is sporting a protective skin on the screen. It appears to be very well made, and comes with a 30-day money back guarantee. At $10 each plus $2.25 shipping per order, I'll probably order a few more as stocking stuffers for the coming holidays.