I used the Microsoft Surface pen. I was initially doubtful about it, especially with the cost, but it is definitely worth it for sketching/writing. The handwriting recognition (conversion to text) isn't amazing - or, to be fair, it hasn't gotten used to my writing yet. I think there's probably an element of the program getting used to your writing input and "learning" what you mean. But it's really great for drawing. The screen is sensitive to pressure, so you get darker and slightly thicker lines the more you press while using the pen. It also senses tilt, so like a real pencil, if you hold it at an angle while drawing, you get a substantially larger shading area. And conversely, if you hold it at a right angle, you get a thin precise line. I used the included basic sketching program that came with the OS. I've downloaded some more advanced art programs, and I'm curious to see how they perform once I learn how to use them.