I would drive out to a beautiful, secluded spot I know on the Colorado river, pitch a tent, and spend my final hours watching the pelicans and the other water birds, and swimming with the huge brown trout there.
Oh, and I'd tell my kitties that I love them and find a good home for them before I left.
I also might travel to DC and assasinate the most digusting politician I can find. (So many choices, so little time)