This is Sister, a beautiful, complex cat both in coloring and in temperament. She will stand on her hind legs to get closer to your hand, and her direct gaze begs communication. Her coloring was a great challenge to tackle; it's brown, grey, black, beige, and the colors that dominate often change in different lighting. She's also got beautifully colored eyes and a split-color face.
I used Adobe Illustrator to free-hand trace her, and then spent a lot of time on her coat - image attached shows the layers of vectors that were just the initial stages of the coat process.