Another reason you shouldn't take this personally is that we know we make lots of mistakes. It's alarming how often the last group to make it over the threshold for interviews ends up being one that we fund. That means there are surely other good groups that fall just below the threshold and that we miss even interviewing.
http://ycombinator.com/whynot.html
We're trying to get better at this, but it's practically certain that groups we rejected will go on to create successful startups. If you do, we'd appreciate it if you'd send us an email telling us about it; we want to learn from our mistakes.
Y Combinator team
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My pitch was WikiTorrents.org, which is user-created lists of downloadable videos.
If you want to help me with some seed money, regardless of amount, maybe I can turn this whole thing into a positive. Email me at citizenkeys AT gmail DOT com .
Here is the WikiTorrents.org collection of YCombinator applicant videos: http://wikitorrents.org/wiki/ycombinator_applicants