Motorola V600
How can I delete pre-installed pictures and tones?
Essentially, the guy determined that making a fake, empty text file with the same name and extension is the key. After using Mobile Phone Tools to move it to the root directory on the V600, the V600 will recognize it as a corrupt file and allow you to delete it. Since you overwrite the original file they both get deleted. They have complete lists of all the movies, images, and animated GIFs so you can "clean it out" nicely.