When I first started to read this, I thought "Jeez... that's a little obvious, Andy. Hardly worth an article." 
Now that I see how some folks are trying to randomize data, I have to admit that such a short and sweet article about it is well overdue. 
I don't believe that anyone will come up with a method that is either faster or more consistently random than just doing the ORDER BY NEWID()... but it is fun to watch folks try. 
--Jeff Moden
RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
First step towards the paradigm shift of writing Set Based code:
________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
Change is inevitable... Change for the better is not.
Helpful Links:
How to post code problems
How to Post Performance Problems
Create a Tally Function (fnTally)