These days, we're all about anything that's free. And when what's free happens to be an annual, venerable SF event - an institution in many ways - we're all about it. Yep, it's Stern Grove Festival time again, and it's kicking off this weekend beneath the eucalyptus trees in the Grove on 19th Avenue and Sloat (which, for festival newbies, is not to be mistaken for Golden Gate Park). This season's performers run the gamut - there's folk, opera, ballet and rap in the mix. Get excited for Roberta Flack, the SF Symphony (July 5), Lyrics Born (July 26), Joan Baez (July 12) and the SF Ballet (August 16). So grab a blanket and head out to the Sunset to enjoy some good, free summer fun.