Before I joined my university, I was wondering about the same question.. what the heck is the difference between a computer scientist and a computer engineer? Well, couldn't find a nice answer about it. Even while studying, the answer didn't reveal itself clearly.

I have recently found an interesting article about it.
http://java.dzone.com/articles/computer-engineer-vs-computer

I don't believe this article is complete...this guy talked only about 'programming' side and did not talk anything about hardware related stuffs. However, yet, I think the article worths a quick reading.

To explain the difference between science and technology, I always refer to the fact that all nations now know the science of nuclear power plants, not all are capable to build it.This guy also dragged a similar example

It took a handful of scientist to come up with an atom bomb, but it took countless of engineers to work out everything else