My initial thoughts would be "what if everyone comes back?" With that in mind, I'd do the following:
1) Make sure not to cause a mess around my home/neighbourhood, which may draw suspicion towards me should everyone return.
2) Stockpile huge amounts of cash, jewelry, cigarettes, alcohol, and various meds (painkillers, etc).
3) Get electricity running by nicking solar panels off people's roofs (I know a few houses nearby that actually have them), and hooking up a generator for those overcast days.
4) Travel around destroying buildings that belong to organisations I don't like/agree with.
5) Do what Guy Fawkes failed to do.
6) Cause the extinction of pigeons, with fire.
7) Raise an army of cats to do my bidding (may help with the above).
8) Watch every movie and TV program I always wanted to watch (on DVD), and play every video game I always wanted to play.