‘The Pixar Theory:’ Are All the Pixar Movies Connected?

I'm a huge fan of Pixar.  I don't think I've seen a single thing come out of that studio that I haven't liked (side note: Cars 2 is not NEARLY as bad as everyone says it is).  Recently, a theory has been circulating around the Internet that blows my mind every time I read it.

Basically, The Pixar Theory states that the past 14 Pixar films all occur within the same universe, on planet Earth, at different periods in time (yes, even Monsters, Inc. and Cars).  I highly encourage you to read the full theory, but here are some of my favorite parts:

• The old witch in "Brave" is Boo from "Monsters, Inc."
• "A Bug's Life" takes place after "Wall-E" helps regrow life on Earth.
• The toys from "Toy Story" and the machines in "Cars" came to life after absorbing the Zero Point Energy created by Buddy, the bad guy in "The Incredibles."

So, do you think there's something to this theory, or is it just a bunch of nonsense?