I am often asked about courses after COS 109 -- courses that go deeper into CS or other aspects of computing, or other courses about technology and society. Here are some suggestions for Spring 2010. I don't have first-hand experience with most of these, but I know and can recommend the people teaching them. I'm happy to talk more about the courses, or help connect you with better sources of information than Course Offerings.
COS 116, The Computational Universe (ST). A more orderly and "scientific" look at some of the computer science aspects of 109, but still with a focus on computers in society.
COS 126, General Computer Science (QR). This is the basic intro course for CS majors, the certificate in applications of computing, the SEAS programming requirement, etc. If you liked the more technical end of 109 and found the programming more interesting than terrifying, 126 is a good bet; it's definitely the best way to take the next step if you think that CS or the certificate might be an option, or if you just want to try the next course.
FRS 120, Life on Mars -- Or Maybe Not (SA)
FRS 166 Fundamental Ideas of the Information Revolution: Insights into Technology, Language, and Biology (QR)
ELE 102, New Eyes for the World: Hands-on Optical Engineering (ST)
ELE 386, Cyber Security (STX)
ELE 491, High-Tech Entrepreneurship
MAT 190, The Magic of Numberse (QR)
AST 203, The Universe (QR)
CEE 262, Structures and The Urban Environment (ST)
EGR 277, Technology and Society