I can't believe this...6 pages of "gadgets" and not one person mentioned the "gridlines" ruler system. I love love love mine. It was pricey but worth every penny. It does not slip and I don't have to crawl my hand up the ruler, just position and cut. Perfect cuts every time.
The other thing I love that was mentioned is the bloc loc ruler, don't do hst's without it.
I will be putting the big look and the clapper on my list now too. Thanks ladies!