I'd be very curious about the viability of clients who approach you in a coffee shop. Seems like you'd get an awful lot of, "So hey, I have this idea that's like Facebook and Youtube combined and I think it could be the next big thing".<p>That's not to say you won't ever find a good client in a coffee shop, but I suspect it has a lower viability rate than a Craigslist ad, and at least on Craigslist I don't have to spend any real time talking to the people who are clearly not serious clients.