Wow, my excitement for this downloadable software couldn't be higher. Arguably the best piece of DS homebrew is getting an official upgrade and release on the eShop, complete with the ability to draw 3D paintings.
That might be old news, but I just saw the latest blog entry from Collecting Smiles that talks more about the software and gives a sample 3D painting for people to download and view on your 3DS:http://www.collectingsmiles.com/news/colors-3d-dev-diary-%E2%80%93-painting-in-3d/
Check it out, and if you haven't used Colors! before take a minute to see Munin's other images that were created using the DS version. (A link is also provided to his profile on the Colors! blog, and you can see a full replay of how each image was created if you mouse-over one of the paintings.)