Being on a big, slow ship doesn't sound appealing until the water gets choppy. Those fast little speedboats can't handle rough water. The big tanker, says Broadpoint AmTech analyst Brian Marshall, is IBM (IBM). But while the water is calm, investors looking for more immediate returns, he says, should look at IBM's business partners such as NetApp (NTAP). With the market now in correction, the conditions may be saying — to quote Chief Brody in