Well if the world was not completely devastated (I.E not nuclear-attack) and I am the very last living thing (Spare plants and micro-organisms) then I'd probably just do whatever I wanted, run naked through parliament house, sleep in a different bed in a different house every night, go on absolute road-rage, build a statue of me, by me dedicated to me. And I'd try to improve my skills in areas such as cooking, art etc. Then I'd probably either get extremely lonely or go extremely crazy after a while. Though it would be cool if you knew that an unexplainable, natural pheneomena was about to occur that just killed all animals in a vicinity (Kind of like that Dirk Pitt novel Shockwave *Reading at the moment don't spoil!*) and you had the only bunker in existence that could save you, but it had room for 2 and only you knew about it. That way not only could I continue the human race but also get jiggy with any girl I please (If they believed me) in the name of uh, human race prolonging procreation (Giggedy).