Maybe an extension of the "Meetup" (meetup.com) groups in every city currently going on (at least here in the USA).
Of course we'd need females who are good at organizing events because us dumb men couldn't put together a pot luck or farmers market if we tried.
Oh well, it was a nice idea. Since there are no girls in the Bitcoin world. (Except BitcoinChick - hi honey!)
Gay people are even better
In addition to good old street markets, every country has at least one popular web portal where people can buy and sell used goods, and we should make those for bitcoin too.
Easy access to high traffic of goods and services.
A serious bitcoin exchange company in my own country is already working on doing this and I think its a low threshold alternative to get those coins rolling