For a sampling, check out City Magazine
I like the summer festivals, East End Festivals, Johnny's Irish Pub, Veneto's Pizza, Pommodoro's Restaurant, East Ave and Alexander area, Water Street Music Hall, the Public Market, Charlotte Pier, Little Theatre, Moonbeams, Dinosaur BBQ, Park Ave on a sunny lunch day, Rochester Amerk hockey, Red Wings baseball, the High Falls area, Milestones, free concerts at Manhattan Square Park (from Crash Test Dummies to Dickie Betts, to Taj Mahal), Bills Training Camp, and of course Nick Tahoes Garbage Plates....
Short trips to Letchworth Park, Finger Lakes wine trail, Watkins Glen Park or Raceway, Hamlin Beach, Canal Days in Brockport and Fairport, Niagara Falls, Turning Stone Casino, the Erie Canal bike path, canoeing, kayaking, water skiiing, jet skis on Irondequiot Bay, and cross country skiiing in Ellison Park.
If I really get bored, I can make it from my driveway to the Lincoln Tunnel in 5 1/2 hours, Alex Bay or Toronto in about three hours.
But other than that there really isn't sh-- to do in Rochester.