It's called Pencil Test Plus and think perfect for rough animation tests. It's completely free and I believe it to be unique in how it lets you mimic the old traditions animation techniques. To check it out just visit
Don't forget to watch the tutorial link first(located on the top right of the web page). Essentially what this tool does is allow you to flip through animation cell sheets like you would in the old days. I really hope you guys enjoy using this software! If you do enjoy it please feel free to share it with classmates, coworkers, and fellow animators, it would be much appreciated!
Happy animating!