Online Mii Creator
Found 25th May 2008
If you would like something a bit more interesting for your avatar at the Wii Talk forum, why don't you create a Mii image and save the image as your avatar.
Its just a bit of fun....! Unfortunately there is not a function to be able to save your Mii creation, but if you use the "Print Screen" key on your keyboard you can paste your image into your image editor and then save your Mii creation locally.