I think the good people at BP are overthinking this whole blown-well thing in the gulf. They're trying all these high-tech solutions to capture the oil, with expensive equipment and untried machinery. What they really need is a very, very large sturdy plastic sheet, with weights around the edges, and a tube coming up from the middle, oh, a few yards across. All they have to do is spread the sheet out and let it sink into place over the blown well. The pressure of water on the inside will be the same as the pressure on the outside, so it shouldn't be too tough to get it positioned over the well. The weights will suffice to hold it in place. Then the pressure inside will increase as the oil spews into the space under the sheet; this will raise the sheet up some and keep it off of the damaged well, while the oil, which is lighter than the surrounding water, will make its way up the tube to the surface, where it can be collected by ships already in place.
It'd probably be cheaper than all these failed machines, too.