I would not recommend gratuitous weirdness actually. The Airbnbs' cereal boxes were interesting because they were an organic part of an impressive story, not just a prop.
The best way to stick out is to seem like you deeply understand your domain and your users. That is (unfortunately) a surprisingly rare quality.
I have added this link to my list of blog entries about the YC Interview experience, bringing the total number of entries to 8 ( http://ycuniverse.com/interviewees.php ). If you have an interview lined up, I would read all of those upfront, study all of the known companies and founders that YC has already funded ( http://ycuniverse.com/ycombinator-companies.php ) and use all that information to your advantage.
College admissions work the same way. So does getting a tenure-track position with a PhD in physics. Or a PhD in philosophy, for that matter. You can probably filter out the obvious bozos with a high degree of accuracy, but it still leaves a huge number of smart, capable people to choose from. Result: crapshoot.
Hats off to YC if it can figure out a way to solve this problem — and please, share the solution with university hiring committees and admissions offices!