Share 'So many educational opportunities; how do you choose?'

Hey all, I get a whole heap of solicitations to join professional organizations and attend conferences, and I'd love to hear your input on which ones are worth the investment. If you only had the resources to become a member of one group, or sign up for one conference/seminar, which would you choose, and why? Is it the networking, the opportunities for info-gathering, the members/attendees-on...