This show really is a two-for-one, with the UNC Sailing Club deciding their 2004 fundraiser should also benefit the ArtsCenter in Carrboro. If the good causes weren't enough, take a look at the diverse roster of bands contributing to the effort, with hummable pop from Roman Candle and The Never, acoustic work from Spencer Acuff, Jennyanykind 's haunting country blues, and folks that sprawl all over the musical map like metal-tinged Marat and neo-romantics Neverending. Life preservers optional. Music starts 8 p.m. Tickets $5 in advance at The ArtsCenter, $4 for ArtsCenter members or $7 at the door. See www.rocktheboat04.com.