Even if your boat has a head with a shower, nothing beats taking a shower in the cockpit after a swim, or when it's so bloody hot you need a refreshing rinse. Single-valve "cold" shower assemblies take the least space. If you have a water heater, or think you might be installing one in the future, you might as well install a dual-valve hot/cold shower. This installation assumes a pressurized, cold freshwater system plumbed with reinforced PVC tube. While Scandvik, Shurflo and Whale all make transom showers, we chose the Heater Craft Aquatik 803SB (defender.com, $110) for a couple of reasons. It has a convenient hot/cold mixing valve and a long, 10-foot hose. Even better, it has a sexy, curvy European look we just couldn't resist.