When you start having a lot of money to manage, it becomes more and more difficult to find good ideas that can be executed on such a large scale.
Divide the fund internally into sub finds and make each one of them responsible for a part of the money.
The merchant can offer free or very cheap delivery, while the customer participating gets large discounts.
Offer customers to help you deliver other packages in their neighborhood for a significant discount. If they participate, they come and pick up their order, plus all the orders in their neighborhood, and deliver them for you.
Automated and cheap.
Used many micro drones all connected to each other wirelessly with the central “brain” controlling them and use to dispatch small but effective explosives all at once, directed at specific targets.
Make the screen function more like a real window.
A screensaver showing a beautiful scene and behaves like a real window to that scene would: when you move or turn your head the displayed scene will change to reflect your point of view of the scene as you would see it through a real window. The built-in camera can be used to track your movements.
Make the world prettier, more fun, and exciting.
Use genetic engineering and/or special nutrients and/or lightwave length sensitivity, and/or combinations of the above (and more) to get plants and flowers having many and “unnatural” colors even withing one plant.