there are a number of settings that make a texture repeat like that, the most obvious is the ‘repeat’ setting of the texture’s wrap mode : http://unity3d.com/support/documentation/ScriptReference/Texture-wrapMode.html
but it also has to do with the UV’s of the model itself. the built-in cube is set up to repeat on each face like that.
from your screenshot, it looks more like you’re using syphon to receive a texture source on the cubes, not as a projector- but it’s hard to tell what’s going on from the screenshot.
if you can post a small example scene (in a zip file) i can take a look.