It goes without saying, but the LSAT is massively important. And, personally, I was scoring mid-to-high 170's the two weeks before the actual test, taking 6 practice tests in that time, and scored high 160's on the real test, and I don't really think I "choked." A lot of it has to do with the questions you receive on the test. It was the difference between (I think) schollies to M Law and paying full price (although I may be mistaken and overly confident in the idea that a higher LSAT in the mid-170's would've gotten me a nice schollie)
here's one vote for "John Beilein's head in a Futurama jar"