Digital Art Frame: High Resolution Screen w/Arduino?

I'm currently doing research and working on an open source digital art canvas (aka frame) project and wondering if anyone in the forum has built one with the arduino? If so, please share your learnings. I'm planning to eventually put together a wiki that contains DIY tutorials and resources in order hopefully get more digital art frames out into the world. If you're curious and want to follow along, here's a Tumblr that I recently started to collect ideas http://osartz.tumblr.com/.

Answers or resources for the following would be greatly appreciated.

Also, if you can think of any neat art-related features that a screen might have, please reply with 'em.

Note: Not that you probably care in an Arduino forum, but I'm planning to build a resource for Raspberry Pi as well.

Why do people come and ask about large screens and/ or video when these are things for which Arduinos, particularly the "entry level" ones are clearly not suited? Why is that not immediately obvious?

A Raspberry Pi is cheaper than the more sophisticated Arduinos, and at least as functional. This is the minimum required for any serious graphic project.

I suppose because folks like pushing limits and it never hurts to ask. Updated the post above to small -medium sized screens since these would also be useful. Still accepting learnings and experiment details.