In the Valley, going out in public without a canned, 30-second spiel for your latest project — the famed "elevator pitch" — is like not wearing underwear. You can do it, but you might embarrass your mom if someone catches you. We went to BarCampBlock, last weekend's nerdathon in Palo Alto, and tested people on the street. Every single one had his pitch at the ready, some delivered more smoothly than others. Did any of them convince you, readers? Tell us in the comments.