You could do a lot of awesome things

No one can see you if you don't want to be seen

You can go through walls and therefore enter whichever house you want

Watch alive human people having sex in their bedrooms (better than porn)

Travel to any place on Earth

Fuck other female/male ghosts (whichever you prefer)

Terrorize some living people if you hate them

You can go to the deepest depths of ocean because you don't need to breath

Live for eternity or at least until Earth explodes and therefore see how the world and technology will advance

etc
etc