A few year ago, I created a list called "The Top Ten Things You Could Do After You're Dead". I've expanded this list with the websites below that might challenge your imagination:
Perhaps, you could be a resident spook on a paranormal TV show like "Ghost Hunters", "Paranormal State" or "Rescue Mediums". Every week you would impersonate a local entity or lost soul. Having established yourself, you would move up to your own "Haunted Funhouse" in Niagara Falls or California.
You could also opened up a human exorcism company like in the movie Beetlejuice.
A very creative spirit could haunt places like "golf courses" and mysterious government projects like "Area 53".
Maybe, you could protect earth from deceptive aliens or do good deeds as a guardian angel.
In meantime, have a safe, happy Halloween.
St Johns