It is a well-settled fact that melons give guys boners, what scientists hope to prove is that more kind of melons than we thought can achieve this end. Watermelon, the official vodka receptacle of Independence day, contains citrulline, an amino acid which can trigger a process similar to the effects of Viagra. "Watermelon may not be as organ-specific as Viagra, but it's a great way to relax blood vessels without any drug side effects." Pro tips: most of the citrulline is found in the rind, and yellow-fleshed watermelons have the highest concentration. Oh, and there's no possible way you're eating enough melon to affect your wang. You'd need to eat about 6 cups of watermelon to get any effect, and watermelon's diuretic power would problematize such effects. In conclusion, the most sure-fire ways to get erections are the most time honored: porn and riding the bus.