1. http://en.wikipedia.org/wiki/Grey_goo

2. http://www.worldwidewords.org/turnsofphrase/tp-gre3.htm

Grey Goo is when matter in the universe can be terned into a bunch of goo.

I think that we should build a machine that sucks up all the matter in the universe. If we could get a group of enginers and get stainless steel Chromium(a resource that is on our planet), then we would conquer the fear of "grey goo." We wouldn't have to worry about the grey goo destroying mankind and leaving our planet a desert wasteland.

3. Self-replication is much different from cloning. Cloning is when someone clones someone else. Self-replication is when something doubles itself like reproduction. I think that Self-replicating is more dangerous because we really can't control it. We can control cloning.