What’s sweeter than an outdoor showcase of some of the city’s finest indie pop and rock? One that’s got free ice cream cones, that’s what. Charleston record label Hearts & Plugs’ Summer Shindig was a fine celebration of all-things sunshiney, complete with a nine-band lineup that persevered in the sun after a brief but battering downpour, girls and boys adorning fresh floral headdresses, and complimentary scoops of Jeni’s Splendid Ice Creams. It all went down a treat last Sat. June 28 at King Dusko, and it was interesting to watch how the musicians collaborated with one another. While they also fronted their own sets, Nick Jenkins played a lot of drums, including Michael Flynn’s, Grace Joyner joined in for backup vocals with Run Dan Run, and the Elim Bolt crew backed up Gold Light. The six-hour show passed swiftly by, with Brave Baby closing things down to a packed backyard. Label founder and director Dan McCurry not only pulled off a damn delightful time had by all, he also sent everyone home with a free Hearts & Plugs sampler to keep listeners floating long after the music stopped.