Since quitting their day jobs two years ago, the four singing zanies of Da Vinci’s Notebook are rapidly becoming one of the premier comedy/a cappella groups around. The songs work—tunes such as “Another Irish Drinking Song,” “Liposuction,” and, of course, “Enormous Penis”—because the harmonies and arrangements are both smart and stellar. Baritone Greg “Storm” DiCostanzo, second tenor Paul Sabourin, first tenor Richard Hsu, and bass Bernie Muller-Thym take as much care with crafting the intricate harmonies as they do making sure the jokes play. But they’re also capable of providing so-called “real” music, which is part of what distinguishes a DVN show from a “Weird Al” concert. Tonight the band hosts a release party for its latest CD, Brontosaurus. “Nobody will be spared from the mocking,” declares Sabourin, “from Irish drinkers to folk music to Internet porn to Heather Graham.” Heather may not be at the show, but you should go. Expect to laugh and fall in love at 7:30 p.m. at the Birchmere, 3701 Mount Vernon Ave., Alexandria. $19.50. (703) 549-7500. (Dave Nuttycombe)