Often where there is live music, there is alcohol. But the organizers of RockSoberFest think that folks should be able to have fun without the presence of mood-altering substances. So they created a drug-free music festival, which will be held on September 28, 3–9 p.m., at the Sonoma-Marin Fairgrounds in Petaluma. The lineup includes The Happys, Venus in Scorpio, Tyler Allen, Paul Hayward, and others. Besides music, there also will be fellowship meetings for those in addiction recovery. See rocksoberfest.org for details, and to purchase tickets, which are $10–$18.