Apparantly after going for help after cutting the line which kept him and his friend from drifting apart in the open water. I couldn't begin to imagine going through something like this. Boat sinks, Texas man survives 30 hours in Gulf - Yahoo! News
I really wonder what the hell happened to where they didn't notice the leak until the engines were already contaminated, why the radio didn't work, and whether they were really just drinking diet coke. Horrific story.
Glad he made it. Had to be hard to leave his friend like that. Boy Scout tip if you are in water without a life jacket: you tie off the legs of your pants and hold them upside down. Swim underneath them and blow air into the waist to inflate them. Now you have a flotation device. Note: this is hard as hell to do.
Depends on the material of the pants, and you have to keep scooping new air in every minute or so. Better than nothing.
I've never tried it in salt water. Might be a tad easier. I also sink like a stone, so that might make things a tad harder on me.