Walmart offers the Eccotemp L10 Portable Outdoor Tankless Water Heater for $174.59 with free shipping. (Amazon and Home Depot charge the same.) That's tied with our mention from two weeks ago and the lowest price we could find by $22. It delivers up to 2.6 gallons per minute of hot water ranging from 80-145 degrees Fahrenheit.

Update: The price has increased at Walmart; however, Amazon and Home Depot still offer it for the same price. Note that Amazon is currently on backorder.