Scognito is working on Wiicross, the game is not out yet but there is an online level editor available.

Release notes:

Finally today I decided to write a post for my next upcoming homebrew game for the Nintendo Wii and Gamecube: it is called Piero’s Wicross.

As the name suggest it is based on a popular puzzle game Mario’s Picross, a game based on an existing puzzle game called Nonogram.

Thanks to http://wiibrew.org for the news.

http://scognito.wordpress.com/2008/09/04/new-wiigamecube-homebrew-is-coming-pieros-wiicross/