First, I wouldn't claim that there is absolutely no possibility for intelligent design. I'd say that it is highly, highly unlikely. The probability of there being a designer or a guiding intelligence in nature is on par with the probability of there being a magical man that flies around the world once a year to deliver presents to good children and coal to bad children. Not impossible per se, but highly improbable.
Also, there is no evidence to suggest that intelligence can exist outside of the physical world, nor is there any particularly compelling reason to believe that it could. To the best of our knowledge, sentient intelligence exists as a result of a lengthy natural process called evolution by natural selection.
The illusion of design in nature is persistent because people have a tendency to an
thropomorphize the universe. Besides, what is it about the universe that suggests design to you, exactly? Is it the vestigial organs found in myriad species? The cruel caprice of nature? Is it the precarious orbit of our planet around the sun? The sheer randomness of the universe in general? Colliding galaxies? Black holes? Exploding suns?
Frankly, if there is a designer, he is incompetent and should be out of a job--especially in this economy.