Did you miss Christian Crumlish at IxD10? You're in luck: this month's BayCHI (Bay Area Computer Human Interaction Group) meeting features a free talk from Christian, plus a look at the past 20 years of BayCHI and a call for ideas on how we can improve the organization.7:30pm: 20+ Years of BayCHI and Counting...BayCHI Steering Committee MembersBayCHI was founded over 20 years ago, and has supported the growth of several new professions in proximity to many vibrant technology corporations and universities. We'll review a few of our accomplishments along the way, and with the audience, interactively incorporate your ideas in creating the next 20 years for BayCHI.8:30pm: Designing Social Interfaces: 5 Principles, 5 Practices, 5 Anti-PatternsChristian Crumlish, Yahoo!Designing for social interaction is hard. People are unpredictable, consistency is a mixed blessing, and co-creation with your users requires a dizzying flirtation with loss of control. Christian will present the dos and don'ts of social web design using a sampling of interaction patterns, design principles and best practices to help you improve the design of your digital social environments.There's also a pre-meeting dinner in Palo Alto. Details on the BayCHI website at http://www.baychi.org/calendar/20100413/