Don't laugh, but I've landed some consulting/side gigs (most recently an I.T. project review with a recommendations report deliverable), based on people that I've met while out socially, and also intro's from people that I know that I run into socially. However, when out socially, I never start off by selling my services, but by having regular conversations, asking them what they do, et cetera.
I also blog about interesting topics in the Caribbean (which MSM rarely touches, at least in my neck of the Caribbean woods), and I use that as a convo starter when people ask me what I do (citizen journalism personally, CTO professionally), and what background I'm from (I.T. and business/commercial roles).