Also, you might like Recettear: An Item Shop's Tale. http://www.gamefaqs.com/pc/604893-recettear-an-item-shops-tale
You don't run an intergallactic delivery service like in Gazillionaire, but it's still a fun simulation/adventure game. It reminds me of Harvest Moon but instead of farming you run a shop and decide how to merchandise it. It also works great with a gamepad, if you have one, since you get to run around randomly generated dungeons to find loot for your shop.