Van posts in his blog about Intentional Friend Making. For those of you who visit these types of places, you may find this interesting (I don't really care for the bar idea though).
Pay attention to where people congregate and hang out. It could be a coffee shop, it could be a bar, it could be the park, or the library, or a cruddy diner, or the local YWCA, or community center, etc. We should try to spend our time more and more where neighborhood people spend their time.