Rembrandt. Picasso. Me. As they say on Sesame Street "which of these things is not like the others?" Assuming the "like" is artistic ability, then it's definitely me.
Whereas these other guys were famous for their artistic skills and vision, mine runs more to the stick figure school of drawing. Luckily we've found the self-described world's first multi-platform stick animation program, Stykz. It's a frame-based tool that lets you compose your animation as individual "cels" and then run them together. It uses "onionskinning" to let you compare your current frame with the preceding one, making sure that your animation rolls smoothly from frame to frame. It's got a full complement of tools that let you manipulate your stick figures and other on-screen elements. You can even have multiple animation documents open simultaneously and cut-and-paste between them. That means you can create your masterpiece and its sequel at the same time. Then you just sit back and wait for the royalties to come rolling in. Or not.
Stykz is available for Mac (OS X 10.4+) and Windows (XP) as a "public beta", with a Linux "internal beta" currently under development and going public soon.