Nwancat by Romano58 is basically Nyancat for Wii plus source code available.

Nwancat v1.0 www.nintendomax.com
Watch this video on YouTube.

Thanks to http://nintendomax.com/viewtopic.php?t=14120&f=54 and http://wiibrew.org/wiki/Nwancat for the news.

http://pouet.net/prod.php?which=58348