To commemorate the ninth anniversary of the 9/11 terrorist attacks on New York City and the Pentagon in Washington, DC, the S.B. Sister Cities and the S.B. Music Club groups are hosting a September 11 Memorial Concert this week. Among the group of scheduled performers are Carol Ann Manzi, The Inner Life Gospel Choir, Greek folk pianist George Mamalakis, vocalist Patti Stathis-Langel and a shakuhachi flautist. The peace- and community-oriented concert begins at 3 p.m. this Saturday, September 11, at the Unitarian Society (1535 Santa Barbara St.). Call 964-7559 for more info.