The Mobile Me Gallery interface doesn't support hot-linking to its images. i.e. there is no explicit URL that will allow you to link to a specific image.

The solution is to download the image from the Mobile Me Gallery, then
upload it to a free hosting service, for example ImageBucket, Flickr etc,
which do allow direct access to images.

We apologize for the inconvenience, but there's no reliable workaround the
Mobile Me Gallery restrictions.