There are only 97 days between Memorial Day and Labor Day. So little time, so much out there to do. Every day between the sunny holidays, we offer a tip —- something fun, frivolous or funky (and maybe even free) to do.

Now that the kiddies are back in school, safe and sound, indulge in a day/night out for the grown-ups at the Rockstar Energy Mayhem Festival tonight at Lakewood Amphitheater. Atlantans will particularly enjoy festival highlight Mastodon, Atlanta-bred metal mongers whose tuneful screams and precision bashing combine thrash, doom, prog and psychedelic metal. Mastodon is joined by Slipknot, Disturbed, Dragonforce, Underoath, Machine Head and others on two additional stages. Tickets: $45-$56.50; $28.50, lawn. 2-11 p.m. tonight. Lakewood Amphitheatre, 2002 Lakewood Way, Atlanta. 404-443-5090, 404-249-6400; www.livenation.com.