Work with a faculty member and join the Google Online Marketing Challenge (held in the spring of every year-see http://www.google.com/onlinechallenge). Google offers ad credits for student teams to develop and run online ad campaigns for real clients and offers prizes for winning teams. Some of the experiences earned in the Google Challenge can translate to other ad networks as well, and firsthand client experience has helped many students secure jobs, internships, and even start their own businesses.