The Gulf oil leak.

If the top kill works its almost all over but if it fails there will be hell to pay.

My solution would be to stick a tent on it. Make a plastic/canvas tube 20 metres across and 200 metres long with a balloon at the top. Add oil removal lines on the sides of the balloon at its widest point. At 200 metres above the sea floor the methane hydrates should not be a problem, the 20 m pipe is wide enough for turbulence to clear them and they will accumulate above the pump-out lines.
Just in case add a small electric UAV tethered to a power supply on the side of the tent/giant pipe. The UAV is inside the balloon. Why there wasn’t a UAV inside the hat structure they put on it beats me. Idiots I guess.
Because its in the oil it will need the same sonar sensors as a PIG, a cleaning robot used in oil pipe lines. This cleaning robot would have a high pressure hot water hose to blast any goop clear of the pump-out lines. The pump-out lines pump down and out. Hydrates and tars float. Provision is added for a solvent input line.
The tent would be anchored to the sea bed with big concrete blocks. This giant pipe wont plug the hole but buys time. It also raises the option of adding a water exclusion collar to the bottom so this tent/ Giant pipe is eventually full of ‘clean’ oil eliminating the dewatering process with the oil. Also if your smart such a collar has an ‘airlock’ waterlock to allow UAV’s to go in and out.
Once this is all over make one tent/ giant pipe with a zipper down the side and store it and the USV’s for any new accident.
Eventually someone will discover that its cheaper to drill in the sea bed on a hydrogen filled dome with telepresence robots replacing the crew. Fully automated sea bed drilling rigs.