I like stuff like this.
There is this popular highway on ramp in my town, I've always wanted to "borrow" people's lawn ornaments and place them on top of the 9 foot tall concrete barrier wall right below the road signs. Like, get dozens of yard gnomes, deers,.. all sorts of crazy lawn stuff you see. And line this wall with it,... do it in the middle of the night,.. hop on the back of my truck to reach the top,...
Make people smile on their way to work that morning,... lol
And I would write the addresses of the lawn ornaments on the bottom of each one that I "borrow" so when the city takes them down,.. they can return them to their owner.