I'm wondering how to put images on the GoogleCode's project homepage. I read the wiki syntax, but I don't know how to integrate that onto the homepage.
It's there, although very well hidden in the "links" section (wtf?):
Plain URLs such as http://www.google.com/ or ftp://ftp.kernel.org/ are automatically made into links.
You can also provide some descriptive text. For example, the following link points to the [http://www.google.com Google home page].
If your link points to an image, it will get inserted as an image tag into the page: