Maineiac

Two guys, of limited intelligence, were on a ship that sank in the middle of the ocean. They manage to inflate a life raft and grab a box of provisions before their ship slips under the surface.

After floating under blazing heat for six days, they ran out of food and water. On the tenth day, bleary eyed and half dead from heat, thirst and starvation, they spotted a small object floating toward them in the water.

As it drew near, they were ecstatic to find that it was an old oil lamp. They grabbed the lamp and rubbed it. Out popped a tired old genie who said, "Okay, so you freed me from the stupid lamp, but hey, I've been doing this three-wishes thing for a while now and quite frankly, I'm burned out. You guys only get one wish and then I'm outta here, so make it a good one."

Without thinking, the first guy blurted out, "Give us all the beer we can drink for the rest of our lives!"

"Fine," said the genie, and he instantly turned the entire ocean to beer.

"Great move, Einstein," said the second guy, slapping the first guy up the side of his head. "Now we're gonna have to pee in the boat!"