Who hasn't experienced the aggravation of running out of hot water halfway through a shower? Maybe the in-laws are in town and using all of your hot water or perhaps you just have a conventional water heater that is about to die. Whatever the cause, a tankless water heater could be the solution you are looking for.The truth is that a tankless water heater actually works and is far superior to the old-fashioned gas or electric "tank" water heaters.