Hot-Can self-heating beverages give boaters piping-hot cocoa, tea, latte and soup, anytime, anywhere. They'll take the chill out of a cold night offshore. Simply push the activation button, shake for 30 seconds and wait. In about three minutes, you have a steaming hot drink (an indicator on the label turns green when ready). The secret? A nontoxic mixture of calcium oxide and water heats the can's contents up to 150 degrees. $1.99; walmart.com.