Which letter replaces the question mark?

A guy is stranded on a desert island all alone for ten years. One day he sees a speck on the horizon. He thinks to himself, "It's not a ship."
The speck gets a little closer and he thinks, "It's not a boat." The speck gets even closer and he thinks, "It's not a raft." Then, out of the surf comes this gorgeous blonde woman wearing a wet suit and scuba gear.
She comes up to the guy and she says, "How long has it been since you've had a cigarette?"
"Ten years!" he says.
She reaches over, unzips this waterproof pocket on her left sleeve and pulls out a pack of fresh cigarettes.
He takes one, lights it, takes a long drag and says, "Man, oh man! Is that good!"
Then she asked, "How long has it been since you've had a drink of whiskey?"
He replies, "Ten years!"
She reaches over, unzips her waterproof pocket on the right, pulls out a flask and gives it to him.
He takes a long swig and says, "Wow! That's fantastic!"
Then she starts unzipping this long zipper that runs down the front of her wet suit and she says to him, "And how long has it been since you've had some REAL fun?"
And the man replies, "Oh my! Don't tell me you've got a computer in there!"