Music Hometown keytar heroes Freezepop have returned from touring the world (okay, Florida, and the Rust Belt) to once again rock Cambridge, with the help of the The Information, The Main Drag, and Michael Hensley. Middle East Downstairs, 8 pm, 18+, $14. Beer Harpoon will hold its St. Patrick's Festival at the brewery on 306 Northern Avenue. Wear galoshes because the floor may well be slick with beer. Harpoon Brewery, 5:30 to 11:00 pm,......